2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
18 #include <linux/sched.h>
19 #include <linux/pagemap.h>
20 #include <linux/writeback.h>
21 #include <linux/blkdev.h>
22 #include <linux/sort.h>
23 #include <linux/rcupdate.h>
24 #include <linux/kthread.h>
25 #include <linux/slab.h>
30 #include "print-tree.h"
31 #include "transaction.h"
34 #include "free-space-cache.h"
36 static int update_block_group(struct btrfs_trans_handle *trans,
37 struct btrfs_root *root,
38 u64 bytenr, u64 num_bytes, int alloc);
39 static int update_reserved_bytes(struct btrfs_block_group_cache *cache,
40 u64 num_bytes, int reserve, int sinfo);
41 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
42 struct btrfs_root *root,
43 u64 bytenr, u64 num_bytes, u64 parent,
44 u64 root_objectid, u64 owner_objectid,
45 u64 owner_offset, int refs_to_drop,
46 struct btrfs_delayed_extent_op *extra_op);
47 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
48 struct extent_buffer *leaf,
49 struct btrfs_extent_item *ei);
50 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
51 struct btrfs_root *root,
52 u64 parent, u64 root_objectid,
53 u64 flags, u64 owner, u64 offset,
54 struct btrfs_key *ins, int ref_mod);
55 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
56 struct btrfs_root *root,
57 u64 parent, u64 root_objectid,
58 u64 flags, struct btrfs_disk_key *key,
59 int level, struct btrfs_key *ins);
60 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
61 struct btrfs_root *extent_root, u64 alloc_bytes,
62 u64 flags, int force);
63 static int find_next_key(struct btrfs_path *path, int level,
64 struct btrfs_key *key);
65 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
66 int dump_block_groups);
69 block_group_cache_done(struct btrfs_block_group_cache *cache)
72 return cache->cached == BTRFS_CACHE_FINISHED;
75 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
77 return (cache->flags & bits) == bits;
80 void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
82 atomic_inc(&cache->count);
85 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
87 if (atomic_dec_and_test(&cache->count)) {
88 WARN_ON(cache->pinned > 0);
89 WARN_ON(cache->reserved > 0);
90 WARN_ON(cache->reserved_pinned > 0);
96 * this adds the block group to the fs_info rb tree for the block group
99 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
100 struct btrfs_block_group_cache *block_group)
103 struct rb_node *parent = NULL;
104 struct btrfs_block_group_cache *cache;
106 spin_lock(&info->block_group_cache_lock);
107 p = &info->block_group_cache_tree.rb_node;
111 cache = rb_entry(parent, struct btrfs_block_group_cache,
113 if (block_group->key.objectid < cache->key.objectid) {
115 } else if (block_group->key.objectid > cache->key.objectid) {
118 spin_unlock(&info->block_group_cache_lock);
123 rb_link_node(&block_group->cache_node, parent, p);
124 rb_insert_color(&block_group->cache_node,
125 &info->block_group_cache_tree);
126 spin_unlock(&info->block_group_cache_lock);
132 * This will return the block group at or after bytenr if contains is 0, else
133 * it will return the block group that contains the bytenr
135 static struct btrfs_block_group_cache *
136 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
139 struct btrfs_block_group_cache *cache, *ret = NULL;
143 spin_lock(&info->block_group_cache_lock);
144 n = info->block_group_cache_tree.rb_node;
147 cache = rb_entry(n, struct btrfs_block_group_cache,
149 end = cache->key.objectid + cache->key.offset - 1;
150 start = cache->key.objectid;
152 if (bytenr < start) {
153 if (!contains && (!ret || start < ret->key.objectid))
156 } else if (bytenr > start) {
157 if (contains && bytenr <= end) {
168 btrfs_get_block_group(ret);
169 spin_unlock(&info->block_group_cache_lock);
174 static int add_excluded_extent(struct btrfs_root *root,
175 u64 start, u64 num_bytes)
177 u64 end = start + num_bytes - 1;
178 set_extent_bits(&root->fs_info->freed_extents[0],
179 start, end, EXTENT_UPTODATE, GFP_NOFS);
180 set_extent_bits(&root->fs_info->freed_extents[1],
181 start, end, EXTENT_UPTODATE, GFP_NOFS);
185 static void free_excluded_extents(struct btrfs_root *root,
186 struct btrfs_block_group_cache *cache)
190 start = cache->key.objectid;
191 end = start + cache->key.offset - 1;
193 clear_extent_bits(&root->fs_info->freed_extents[0],
194 start, end, EXTENT_UPTODATE, GFP_NOFS);
195 clear_extent_bits(&root->fs_info->freed_extents[1],
196 start, end, EXTENT_UPTODATE, GFP_NOFS);
199 static int exclude_super_stripes(struct btrfs_root *root,
200 struct btrfs_block_group_cache *cache)
207 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
208 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
209 cache->bytes_super += stripe_len;
210 ret = add_excluded_extent(root, cache->key.objectid,
215 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
216 bytenr = btrfs_sb_offset(i);
217 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
218 cache->key.objectid, bytenr,
219 0, &logical, &nr, &stripe_len);
223 cache->bytes_super += stripe_len;
224 ret = add_excluded_extent(root, logical[nr],
234 static struct btrfs_caching_control *
235 get_caching_control(struct btrfs_block_group_cache *cache)
237 struct btrfs_caching_control *ctl;
239 spin_lock(&cache->lock);
240 if (cache->cached != BTRFS_CACHE_STARTED) {
241 spin_unlock(&cache->lock);
245 /* We're loading it the fast way, so we don't have a caching_ctl. */
246 if (!cache->caching_ctl) {
247 spin_unlock(&cache->lock);
251 ctl = cache->caching_ctl;
252 atomic_inc(&ctl->count);
253 spin_unlock(&cache->lock);
257 static void put_caching_control(struct btrfs_caching_control *ctl)
259 if (atomic_dec_and_test(&ctl->count))
264 * this is only called by cache_block_group, since we could have freed extents
265 * we need to check the pinned_extents for any extents that can't be used yet
266 * since their free space will be released as soon as the transaction commits.
268 static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
269 struct btrfs_fs_info *info, u64 start, u64 end)
271 u64 extent_start, extent_end, size, total_added = 0;
274 while (start < end) {
275 ret = find_first_extent_bit(info->pinned_extents, start,
276 &extent_start, &extent_end,
277 EXTENT_DIRTY | EXTENT_UPTODATE);
281 if (extent_start <= start) {
282 start = extent_end + 1;
283 } else if (extent_start > start && extent_start < end) {
284 size = extent_start - start;
286 ret = btrfs_add_free_space(block_group, start,
289 start = extent_end + 1;
298 ret = btrfs_add_free_space(block_group, start, size);
305 static int caching_kthread(void *data)
307 struct btrfs_block_group_cache *block_group = data;
308 struct btrfs_fs_info *fs_info = block_group->fs_info;
309 struct btrfs_caching_control *caching_ctl = block_group->caching_ctl;
310 struct btrfs_root *extent_root = fs_info->extent_root;
311 struct btrfs_path *path;
312 struct extent_buffer *leaf;
313 struct btrfs_key key;
319 path = btrfs_alloc_path();
323 exclude_super_stripes(extent_root, block_group);
324 spin_lock(&block_group->space_info->lock);
325 block_group->space_info->bytes_readonly += block_group->bytes_super;
326 spin_unlock(&block_group->space_info->lock);
328 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
331 * We don't want to deadlock with somebody trying to allocate a new
332 * extent for the extent root while also trying to search the extent
333 * root to add free space. So we skip locking and search the commit
334 * root, since its read-only
336 path->skip_locking = 1;
337 path->search_commit_root = 1;
342 key.type = BTRFS_EXTENT_ITEM_KEY;
344 mutex_lock(&caching_ctl->mutex);
345 /* need to make sure the commit_root doesn't disappear */
346 down_read(&fs_info->extent_commit_sem);
348 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
352 leaf = path->nodes[0];
353 nritems = btrfs_header_nritems(leaf);
357 if (fs_info->closing > 1) {
362 if (path->slots[0] < nritems) {
363 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
365 ret = find_next_key(path, 0, &key);
369 caching_ctl->progress = last;
370 btrfs_release_path(extent_root, path);
371 up_read(&fs_info->extent_commit_sem);
372 mutex_unlock(&caching_ctl->mutex);
373 if (btrfs_transaction_in_commit(fs_info))
380 if (key.objectid < block_group->key.objectid) {
385 if (key.objectid >= block_group->key.objectid +
386 block_group->key.offset)
389 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
390 total_found += add_new_free_space(block_group,
393 last = key.objectid + key.offset;
395 if (total_found > (1024 * 1024 * 2)) {
397 wake_up(&caching_ctl->wait);
404 total_found += add_new_free_space(block_group, fs_info, last,
405 block_group->key.objectid +
406 block_group->key.offset);
407 caching_ctl->progress = (u64)-1;
409 spin_lock(&block_group->lock);
410 block_group->caching_ctl = NULL;
411 block_group->cached = BTRFS_CACHE_FINISHED;
412 spin_unlock(&block_group->lock);
415 btrfs_free_path(path);
416 up_read(&fs_info->extent_commit_sem);
418 free_excluded_extents(extent_root, block_group);
420 mutex_unlock(&caching_ctl->mutex);
421 wake_up(&caching_ctl->wait);
423 put_caching_control(caching_ctl);
424 atomic_dec(&block_group->space_info->caching_threads);
425 btrfs_put_block_group(block_group);
430 static int cache_block_group(struct btrfs_block_group_cache *cache,
431 struct btrfs_trans_handle *trans,
434 struct btrfs_fs_info *fs_info = cache->fs_info;
435 struct btrfs_caching_control *caching_ctl;
436 struct task_struct *tsk;
440 if (cache->cached != BTRFS_CACHE_NO)
444 * We can't do the read from on-disk cache during a commit since we need
445 * to have the normal tree locking.
447 if (!trans->transaction->in_commit) {
448 spin_lock(&cache->lock);
449 if (cache->cached != BTRFS_CACHE_NO) {
450 spin_unlock(&cache->lock);
453 cache->cached = BTRFS_CACHE_STARTED;
454 spin_unlock(&cache->lock);
456 ret = load_free_space_cache(fs_info, cache);
458 spin_lock(&cache->lock);
460 cache->cached = BTRFS_CACHE_FINISHED;
461 cache->last_byte_to_unpin = (u64)-1;
463 cache->cached = BTRFS_CACHE_NO;
465 spin_unlock(&cache->lock);
473 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_KERNEL);
474 BUG_ON(!caching_ctl);
476 INIT_LIST_HEAD(&caching_ctl->list);
477 mutex_init(&caching_ctl->mutex);
478 init_waitqueue_head(&caching_ctl->wait);
479 caching_ctl->block_group = cache;
480 caching_ctl->progress = cache->key.objectid;
481 /* one for caching kthread, one for caching block group list */
482 atomic_set(&caching_ctl->count, 2);
484 spin_lock(&cache->lock);
485 if (cache->cached != BTRFS_CACHE_NO) {
486 spin_unlock(&cache->lock);
490 cache->caching_ctl = caching_ctl;
491 cache->cached = BTRFS_CACHE_STARTED;
492 spin_unlock(&cache->lock);
494 down_write(&fs_info->extent_commit_sem);
495 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
496 up_write(&fs_info->extent_commit_sem);
498 atomic_inc(&cache->space_info->caching_threads);
499 btrfs_get_block_group(cache);
501 tsk = kthread_run(caching_kthread, cache, "btrfs-cache-%llu\n",
502 cache->key.objectid);
505 printk(KERN_ERR "error running thread %d\n", ret);
513 * return the block group that starts at or after bytenr
515 static struct btrfs_block_group_cache *
516 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
518 struct btrfs_block_group_cache *cache;
520 cache = block_group_cache_tree_search(info, bytenr, 0);
526 * return the block group that contains the given bytenr
528 struct btrfs_block_group_cache *btrfs_lookup_block_group(
529 struct btrfs_fs_info *info,
532 struct btrfs_block_group_cache *cache;
534 cache = block_group_cache_tree_search(info, bytenr, 1);
539 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
542 struct list_head *head = &info->space_info;
543 struct btrfs_space_info *found;
545 flags &= BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_SYSTEM |
546 BTRFS_BLOCK_GROUP_METADATA;
549 list_for_each_entry_rcu(found, head, list) {
550 if (found->flags & flags) {
560 * after adding space to the filesystem, we need to clear the full flags
561 * on all the space infos.
563 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
565 struct list_head *head = &info->space_info;
566 struct btrfs_space_info *found;
569 list_for_each_entry_rcu(found, head, list)
574 static u64 div_factor(u64 num, int factor)
583 static u64 div_factor_fine(u64 num, int factor)
592 u64 btrfs_find_block_group(struct btrfs_root *root,
593 u64 search_start, u64 search_hint, int owner)
595 struct btrfs_block_group_cache *cache;
597 u64 last = max(search_hint, search_start);
604 cache = btrfs_lookup_first_block_group(root->fs_info, last);
608 spin_lock(&cache->lock);
609 last = cache->key.objectid + cache->key.offset;
610 used = btrfs_block_group_used(&cache->item);
612 if ((full_search || !cache->ro) &&
613 block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
614 if (used + cache->pinned + cache->reserved <
615 div_factor(cache->key.offset, factor)) {
616 group_start = cache->key.objectid;
617 spin_unlock(&cache->lock);
618 btrfs_put_block_group(cache);
622 spin_unlock(&cache->lock);
623 btrfs_put_block_group(cache);
631 if (!full_search && factor < 10) {
641 /* simple helper to search for an existing extent at a given offset */
642 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
645 struct btrfs_key key;
646 struct btrfs_path *path;
648 path = btrfs_alloc_path();
650 key.objectid = start;
652 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
653 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
655 btrfs_free_path(path);
660 * helper function to lookup reference count and flags of extent.
662 * the head node for delayed ref is used to store the sum of all the
663 * reference count modifications queued up in the rbtree. the head
664 * node may also store the extent flags to set. This way you can check
665 * to see what the reference count and extent flags would be if all of
666 * the delayed refs are not processed.
668 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
669 struct btrfs_root *root, u64 bytenr,
670 u64 num_bytes, u64 *refs, u64 *flags)
672 struct btrfs_delayed_ref_head *head;
673 struct btrfs_delayed_ref_root *delayed_refs;
674 struct btrfs_path *path;
675 struct btrfs_extent_item *ei;
676 struct extent_buffer *leaf;
677 struct btrfs_key key;
683 path = btrfs_alloc_path();
687 key.objectid = bytenr;
688 key.type = BTRFS_EXTENT_ITEM_KEY;
689 key.offset = num_bytes;
691 path->skip_locking = 1;
692 path->search_commit_root = 1;
695 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
701 leaf = path->nodes[0];
702 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
703 if (item_size >= sizeof(*ei)) {
704 ei = btrfs_item_ptr(leaf, path->slots[0],
705 struct btrfs_extent_item);
706 num_refs = btrfs_extent_refs(leaf, ei);
707 extent_flags = btrfs_extent_flags(leaf, ei);
709 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
710 struct btrfs_extent_item_v0 *ei0;
711 BUG_ON(item_size != sizeof(*ei0));
712 ei0 = btrfs_item_ptr(leaf, path->slots[0],
713 struct btrfs_extent_item_v0);
714 num_refs = btrfs_extent_refs_v0(leaf, ei0);
715 /* FIXME: this isn't correct for data */
716 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
721 BUG_ON(num_refs == 0);
731 delayed_refs = &trans->transaction->delayed_refs;
732 spin_lock(&delayed_refs->lock);
733 head = btrfs_find_delayed_ref_head(trans, bytenr);
735 if (!mutex_trylock(&head->mutex)) {
736 atomic_inc(&head->node.refs);
737 spin_unlock(&delayed_refs->lock);
739 btrfs_release_path(root->fs_info->extent_root, path);
741 mutex_lock(&head->mutex);
742 mutex_unlock(&head->mutex);
743 btrfs_put_delayed_ref(&head->node);
746 if (head->extent_op && head->extent_op->update_flags)
747 extent_flags |= head->extent_op->flags_to_set;
749 BUG_ON(num_refs == 0);
751 num_refs += head->node.ref_mod;
752 mutex_unlock(&head->mutex);
754 spin_unlock(&delayed_refs->lock);
756 WARN_ON(num_refs == 0);
760 *flags = extent_flags;
762 btrfs_free_path(path);
767 * Back reference rules. Back refs have three main goals:
769 * 1) differentiate between all holders of references to an extent so that
770 * when a reference is dropped we can make sure it was a valid reference
771 * before freeing the extent.
773 * 2) Provide enough information to quickly find the holders of an extent
774 * if we notice a given block is corrupted or bad.
776 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
777 * maintenance. This is actually the same as #2, but with a slightly
778 * different use case.
780 * There are two kinds of back refs. The implicit back refs is optimized
781 * for pointers in non-shared tree blocks. For a given pointer in a block,
782 * back refs of this kind provide information about the block's owner tree
783 * and the pointer's key. These information allow us to find the block by
784 * b-tree searching. The full back refs is for pointers in tree blocks not
785 * referenced by their owner trees. The location of tree block is recorded
786 * in the back refs. Actually the full back refs is generic, and can be
787 * used in all cases the implicit back refs is used. The major shortcoming
788 * of the full back refs is its overhead. Every time a tree block gets
789 * COWed, we have to update back refs entry for all pointers in it.
791 * For a newly allocated tree block, we use implicit back refs for
792 * pointers in it. This means most tree related operations only involve
793 * implicit back refs. For a tree block created in old transaction, the
794 * only way to drop a reference to it is COW it. So we can detect the
795 * event that tree block loses its owner tree's reference and do the
796 * back refs conversion.
798 * When a tree block is COW'd through a tree, there are four cases:
800 * The reference count of the block is one and the tree is the block's
801 * owner tree. Nothing to do in this case.
803 * The reference count of the block is one and the tree is not the
804 * block's owner tree. In this case, full back refs is used for pointers
805 * in the block. Remove these full back refs, add implicit back refs for
806 * every pointers in the new block.
808 * The reference count of the block is greater than one and the tree is
809 * the block's owner tree. In this case, implicit back refs is used for
810 * pointers in the block. Add full back refs for every pointers in the
811 * block, increase lower level extents' reference counts. The original
812 * implicit back refs are entailed to the new block.
814 * The reference count of the block is greater than one and the tree is
815 * not the block's owner tree. Add implicit back refs for every pointer in
816 * the new block, increase lower level extents' reference count.
818 * Back Reference Key composing:
820 * The key objectid corresponds to the first byte in the extent,
821 * The key type is used to differentiate between types of back refs.
822 * There are different meanings of the key offset for different types
825 * File extents can be referenced by:
827 * - multiple snapshots, subvolumes, or different generations in one subvol
828 * - different files inside a single subvolume
829 * - different offsets inside a file (bookend extents in file.c)
831 * The extent ref structure for the implicit back refs has fields for:
833 * - Objectid of the subvolume root
834 * - objectid of the file holding the reference
835 * - original offset in the file
836 * - how many bookend extents
838 * The key offset for the implicit back refs is hash of the first
841 * The extent ref structure for the full back refs has field for:
843 * - number of pointers in the tree leaf
845 * The key offset for the implicit back refs is the first byte of
848 * When a file extent is allocated, The implicit back refs is used.
849 * the fields are filled in:
851 * (root_key.objectid, inode objectid, offset in file, 1)
853 * When a file extent is removed file truncation, we find the
854 * corresponding implicit back refs and check the following fields:
856 * (btrfs_header_owner(leaf), inode objectid, offset in file)
858 * Btree extents can be referenced by:
860 * - Different subvolumes
862 * Both the implicit back refs and the full back refs for tree blocks
863 * only consist of key. The key offset for the implicit back refs is
864 * objectid of block's owner tree. The key offset for the full back refs
865 * is the first byte of parent block.
867 * When implicit back refs is used, information about the lowest key and
868 * level of the tree block are required. These information are stored in
869 * tree block info structure.
872 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
873 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
874 struct btrfs_root *root,
875 struct btrfs_path *path,
876 u64 owner, u32 extra_size)
878 struct btrfs_extent_item *item;
879 struct btrfs_extent_item_v0 *ei0;
880 struct btrfs_extent_ref_v0 *ref0;
881 struct btrfs_tree_block_info *bi;
882 struct extent_buffer *leaf;
883 struct btrfs_key key;
884 struct btrfs_key found_key;
885 u32 new_size = sizeof(*item);
889 leaf = path->nodes[0];
890 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
892 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
893 ei0 = btrfs_item_ptr(leaf, path->slots[0],
894 struct btrfs_extent_item_v0);
895 refs = btrfs_extent_refs_v0(leaf, ei0);
897 if (owner == (u64)-1) {
899 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
900 ret = btrfs_next_leaf(root, path);
904 leaf = path->nodes[0];
906 btrfs_item_key_to_cpu(leaf, &found_key,
908 BUG_ON(key.objectid != found_key.objectid);
909 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
913 ref0 = btrfs_item_ptr(leaf, path->slots[0],
914 struct btrfs_extent_ref_v0);
915 owner = btrfs_ref_objectid_v0(leaf, ref0);
919 btrfs_release_path(root, path);
921 if (owner < BTRFS_FIRST_FREE_OBJECTID)
922 new_size += sizeof(*bi);
924 new_size -= sizeof(*ei0);
925 ret = btrfs_search_slot(trans, root, &key, path,
926 new_size + extra_size, 1);
931 ret = btrfs_extend_item(trans, root, path, new_size);
934 leaf = path->nodes[0];
935 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
936 btrfs_set_extent_refs(leaf, item, refs);
937 /* FIXME: get real generation */
938 btrfs_set_extent_generation(leaf, item, 0);
939 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
940 btrfs_set_extent_flags(leaf, item,
941 BTRFS_EXTENT_FLAG_TREE_BLOCK |
942 BTRFS_BLOCK_FLAG_FULL_BACKREF);
943 bi = (struct btrfs_tree_block_info *)(item + 1);
944 /* FIXME: get first key of the block */
945 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
946 btrfs_set_tree_block_level(leaf, bi, (int)owner);
948 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
950 btrfs_mark_buffer_dirty(leaf);
955 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
957 u32 high_crc = ~(u32)0;
958 u32 low_crc = ~(u32)0;
961 lenum = cpu_to_le64(root_objectid);
962 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
963 lenum = cpu_to_le64(owner);
964 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
965 lenum = cpu_to_le64(offset);
966 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
968 return ((u64)high_crc << 31) ^ (u64)low_crc;
971 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
972 struct btrfs_extent_data_ref *ref)
974 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
975 btrfs_extent_data_ref_objectid(leaf, ref),
976 btrfs_extent_data_ref_offset(leaf, ref));
979 static int match_extent_data_ref(struct extent_buffer *leaf,
980 struct btrfs_extent_data_ref *ref,
981 u64 root_objectid, u64 owner, u64 offset)
983 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
984 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
985 btrfs_extent_data_ref_offset(leaf, ref) != offset)
990 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
991 struct btrfs_root *root,
992 struct btrfs_path *path,
993 u64 bytenr, u64 parent,
995 u64 owner, u64 offset)
997 struct btrfs_key key;
998 struct btrfs_extent_data_ref *ref;
999 struct extent_buffer *leaf;
1005 key.objectid = bytenr;
1007 key.type = BTRFS_SHARED_DATA_REF_KEY;
1008 key.offset = parent;
1010 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1011 key.offset = hash_extent_data_ref(root_objectid,
1016 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1025 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1026 key.type = BTRFS_EXTENT_REF_V0_KEY;
1027 btrfs_release_path(root, path);
1028 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1039 leaf = path->nodes[0];
1040 nritems = btrfs_header_nritems(leaf);
1042 if (path->slots[0] >= nritems) {
1043 ret = btrfs_next_leaf(root, path);
1049 leaf = path->nodes[0];
1050 nritems = btrfs_header_nritems(leaf);
1054 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1055 if (key.objectid != bytenr ||
1056 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1059 ref = btrfs_item_ptr(leaf, path->slots[0],
1060 struct btrfs_extent_data_ref);
1062 if (match_extent_data_ref(leaf, ref, root_objectid,
1065 btrfs_release_path(root, path);
1077 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1078 struct btrfs_root *root,
1079 struct btrfs_path *path,
1080 u64 bytenr, u64 parent,
1081 u64 root_objectid, u64 owner,
1082 u64 offset, int refs_to_add)
1084 struct btrfs_key key;
1085 struct extent_buffer *leaf;
1090 key.objectid = bytenr;
1092 key.type = BTRFS_SHARED_DATA_REF_KEY;
1093 key.offset = parent;
1094 size = sizeof(struct btrfs_shared_data_ref);
1096 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1097 key.offset = hash_extent_data_ref(root_objectid,
1099 size = sizeof(struct btrfs_extent_data_ref);
1102 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1103 if (ret && ret != -EEXIST)
1106 leaf = path->nodes[0];
1108 struct btrfs_shared_data_ref *ref;
1109 ref = btrfs_item_ptr(leaf, path->slots[0],
1110 struct btrfs_shared_data_ref);
1112 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1114 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1115 num_refs += refs_to_add;
1116 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1119 struct btrfs_extent_data_ref *ref;
1120 while (ret == -EEXIST) {
1121 ref = btrfs_item_ptr(leaf, path->slots[0],
1122 struct btrfs_extent_data_ref);
1123 if (match_extent_data_ref(leaf, ref, root_objectid,
1126 btrfs_release_path(root, path);
1128 ret = btrfs_insert_empty_item(trans, root, path, &key,
1130 if (ret && ret != -EEXIST)
1133 leaf = path->nodes[0];
1135 ref = btrfs_item_ptr(leaf, path->slots[0],
1136 struct btrfs_extent_data_ref);
1138 btrfs_set_extent_data_ref_root(leaf, ref,
1140 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1141 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1142 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1144 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1145 num_refs += refs_to_add;
1146 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1149 btrfs_mark_buffer_dirty(leaf);
1152 btrfs_release_path(root, path);
1156 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1157 struct btrfs_root *root,
1158 struct btrfs_path *path,
1161 struct btrfs_key key;
1162 struct btrfs_extent_data_ref *ref1 = NULL;
1163 struct btrfs_shared_data_ref *ref2 = NULL;
1164 struct extent_buffer *leaf;
1168 leaf = path->nodes[0];
1169 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1171 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1172 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1173 struct btrfs_extent_data_ref);
1174 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1175 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1176 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1177 struct btrfs_shared_data_ref);
1178 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1179 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1180 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1181 struct btrfs_extent_ref_v0 *ref0;
1182 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1183 struct btrfs_extent_ref_v0);
1184 num_refs = btrfs_ref_count_v0(leaf, ref0);
1190 BUG_ON(num_refs < refs_to_drop);
1191 num_refs -= refs_to_drop;
1193 if (num_refs == 0) {
1194 ret = btrfs_del_item(trans, root, path);
1196 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1197 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1198 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1199 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1200 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1202 struct btrfs_extent_ref_v0 *ref0;
1203 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1204 struct btrfs_extent_ref_v0);
1205 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1208 btrfs_mark_buffer_dirty(leaf);
1213 static noinline u32 extent_data_ref_count(struct btrfs_root *root,
1214 struct btrfs_path *path,
1215 struct btrfs_extent_inline_ref *iref)
1217 struct btrfs_key key;
1218 struct extent_buffer *leaf;
1219 struct btrfs_extent_data_ref *ref1;
1220 struct btrfs_shared_data_ref *ref2;
1223 leaf = path->nodes[0];
1224 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1226 if (btrfs_extent_inline_ref_type(leaf, iref) ==
1227 BTRFS_EXTENT_DATA_REF_KEY) {
1228 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1229 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1231 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1232 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1234 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1235 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1236 struct btrfs_extent_data_ref);
1237 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1238 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1239 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1240 struct btrfs_shared_data_ref);
1241 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1242 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1243 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1244 struct btrfs_extent_ref_v0 *ref0;
1245 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1246 struct btrfs_extent_ref_v0);
1247 num_refs = btrfs_ref_count_v0(leaf, ref0);
1255 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1256 struct btrfs_root *root,
1257 struct btrfs_path *path,
1258 u64 bytenr, u64 parent,
1261 struct btrfs_key key;
1264 key.objectid = bytenr;
1266 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1267 key.offset = parent;
1269 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1270 key.offset = root_objectid;
1273 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1276 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1277 if (ret == -ENOENT && parent) {
1278 btrfs_release_path(root, path);
1279 key.type = BTRFS_EXTENT_REF_V0_KEY;
1280 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1288 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1289 struct btrfs_root *root,
1290 struct btrfs_path *path,
1291 u64 bytenr, u64 parent,
1294 struct btrfs_key key;
1297 key.objectid = bytenr;
1299 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1300 key.offset = parent;
1302 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1303 key.offset = root_objectid;
1306 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1307 btrfs_release_path(root, path);
1311 static inline int extent_ref_type(u64 parent, u64 owner)
1314 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1316 type = BTRFS_SHARED_BLOCK_REF_KEY;
1318 type = BTRFS_TREE_BLOCK_REF_KEY;
1321 type = BTRFS_SHARED_DATA_REF_KEY;
1323 type = BTRFS_EXTENT_DATA_REF_KEY;
1328 static int find_next_key(struct btrfs_path *path, int level,
1329 struct btrfs_key *key)
1332 for (; level < BTRFS_MAX_LEVEL; level++) {
1333 if (!path->nodes[level])
1335 if (path->slots[level] + 1 >=
1336 btrfs_header_nritems(path->nodes[level]))
1339 btrfs_item_key_to_cpu(path->nodes[level], key,
1340 path->slots[level] + 1);
1342 btrfs_node_key_to_cpu(path->nodes[level], key,
1343 path->slots[level] + 1);
1350 * look for inline back ref. if back ref is found, *ref_ret is set
1351 * to the address of inline back ref, and 0 is returned.
1353 * if back ref isn't found, *ref_ret is set to the address where it
1354 * should be inserted, and -ENOENT is returned.
1356 * if insert is true and there are too many inline back refs, the path
1357 * points to the extent item, and -EAGAIN is returned.
1359 * NOTE: inline back refs are ordered in the same way that back ref
1360 * items in the tree are ordered.
1362 static noinline_for_stack
1363 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1364 struct btrfs_root *root,
1365 struct btrfs_path *path,
1366 struct btrfs_extent_inline_ref **ref_ret,
1367 u64 bytenr, u64 num_bytes,
1368 u64 parent, u64 root_objectid,
1369 u64 owner, u64 offset, int insert)
1371 struct btrfs_key key;
1372 struct extent_buffer *leaf;
1373 struct btrfs_extent_item *ei;
1374 struct btrfs_extent_inline_ref *iref;
1385 key.objectid = bytenr;
1386 key.type = BTRFS_EXTENT_ITEM_KEY;
1387 key.offset = num_bytes;
1389 want = extent_ref_type(parent, owner);
1391 extra_size = btrfs_extent_inline_ref_size(want);
1392 path->keep_locks = 1;
1395 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1402 leaf = path->nodes[0];
1403 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1404 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1405 if (item_size < sizeof(*ei)) {
1410 ret = convert_extent_item_v0(trans, root, path, owner,
1416 leaf = path->nodes[0];
1417 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1420 BUG_ON(item_size < sizeof(*ei));
1422 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1423 flags = btrfs_extent_flags(leaf, ei);
1425 ptr = (unsigned long)(ei + 1);
1426 end = (unsigned long)ei + item_size;
1428 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1429 ptr += sizeof(struct btrfs_tree_block_info);
1432 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA));
1441 iref = (struct btrfs_extent_inline_ref *)ptr;
1442 type = btrfs_extent_inline_ref_type(leaf, iref);
1446 ptr += btrfs_extent_inline_ref_size(type);
1450 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1451 struct btrfs_extent_data_ref *dref;
1452 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1453 if (match_extent_data_ref(leaf, dref, root_objectid,
1458 if (hash_extent_data_ref_item(leaf, dref) <
1459 hash_extent_data_ref(root_objectid, owner, offset))
1463 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1465 if (parent == ref_offset) {
1469 if (ref_offset < parent)
1472 if (root_objectid == ref_offset) {
1476 if (ref_offset < root_objectid)
1480 ptr += btrfs_extent_inline_ref_size(type);
1482 if (err == -ENOENT && insert) {
1483 if (item_size + extra_size >=
1484 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1489 * To add new inline back ref, we have to make sure
1490 * there is no corresponding back ref item.
1491 * For simplicity, we just do not add new inline back
1492 * ref if there is any kind of item for this block
1494 if (find_next_key(path, 0, &key) == 0 &&
1495 key.objectid == bytenr &&
1496 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1501 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1504 path->keep_locks = 0;
1505 btrfs_unlock_up_safe(path, 1);
1511 * helper to add new inline back ref
1513 static noinline_for_stack
1514 int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1515 struct btrfs_root *root,
1516 struct btrfs_path *path,
1517 struct btrfs_extent_inline_ref *iref,
1518 u64 parent, u64 root_objectid,
1519 u64 owner, u64 offset, int refs_to_add,
1520 struct btrfs_delayed_extent_op *extent_op)
1522 struct extent_buffer *leaf;
1523 struct btrfs_extent_item *ei;
1526 unsigned long item_offset;
1532 leaf = path->nodes[0];
1533 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1534 item_offset = (unsigned long)iref - (unsigned long)ei;
1536 type = extent_ref_type(parent, owner);
1537 size = btrfs_extent_inline_ref_size(type);
1539 ret = btrfs_extend_item(trans, root, path, size);
1542 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1543 refs = btrfs_extent_refs(leaf, ei);
1544 refs += refs_to_add;
1545 btrfs_set_extent_refs(leaf, ei, refs);
1547 __run_delayed_extent_op(extent_op, leaf, ei);
1549 ptr = (unsigned long)ei + item_offset;
1550 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1551 if (ptr < end - size)
1552 memmove_extent_buffer(leaf, ptr + size, ptr,
1555 iref = (struct btrfs_extent_inline_ref *)ptr;
1556 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1557 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1558 struct btrfs_extent_data_ref *dref;
1559 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1560 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1561 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1562 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1563 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1564 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1565 struct btrfs_shared_data_ref *sref;
1566 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1567 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1568 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1569 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1570 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1572 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1574 btrfs_mark_buffer_dirty(leaf);
1578 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1579 struct btrfs_root *root,
1580 struct btrfs_path *path,
1581 struct btrfs_extent_inline_ref **ref_ret,
1582 u64 bytenr, u64 num_bytes, u64 parent,
1583 u64 root_objectid, u64 owner, u64 offset)
1587 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1588 bytenr, num_bytes, parent,
1589 root_objectid, owner, offset, 0);
1593 btrfs_release_path(root, path);
1596 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1597 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1600 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1601 root_objectid, owner, offset);
1607 * helper to update/remove inline back ref
1609 static noinline_for_stack
1610 int update_inline_extent_backref(struct btrfs_trans_handle *trans,
1611 struct btrfs_root *root,
1612 struct btrfs_path *path,
1613 struct btrfs_extent_inline_ref *iref,
1615 struct btrfs_delayed_extent_op *extent_op)
1617 struct extent_buffer *leaf;
1618 struct btrfs_extent_item *ei;
1619 struct btrfs_extent_data_ref *dref = NULL;
1620 struct btrfs_shared_data_ref *sref = NULL;
1629 leaf = path->nodes[0];
1630 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1631 refs = btrfs_extent_refs(leaf, ei);
1632 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1633 refs += refs_to_mod;
1634 btrfs_set_extent_refs(leaf, ei, refs);
1636 __run_delayed_extent_op(extent_op, leaf, ei);
1638 type = btrfs_extent_inline_ref_type(leaf, iref);
1640 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1641 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1642 refs = btrfs_extent_data_ref_count(leaf, dref);
1643 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1644 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1645 refs = btrfs_shared_data_ref_count(leaf, sref);
1648 BUG_ON(refs_to_mod != -1);
1651 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1652 refs += refs_to_mod;
1655 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1656 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1658 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1660 size = btrfs_extent_inline_ref_size(type);
1661 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1662 ptr = (unsigned long)iref;
1663 end = (unsigned long)ei + item_size;
1664 if (ptr + size < end)
1665 memmove_extent_buffer(leaf, ptr, ptr + size,
1668 ret = btrfs_truncate_item(trans, root, path, item_size, 1);
1671 btrfs_mark_buffer_dirty(leaf);
1675 static noinline_for_stack
1676 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1677 struct btrfs_root *root,
1678 struct btrfs_path *path,
1679 u64 bytenr, u64 num_bytes, u64 parent,
1680 u64 root_objectid, u64 owner,
1681 u64 offset, int refs_to_add,
1682 struct btrfs_delayed_extent_op *extent_op)
1684 struct btrfs_extent_inline_ref *iref;
1687 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1688 bytenr, num_bytes, parent,
1689 root_objectid, owner, offset, 1);
1691 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1692 ret = update_inline_extent_backref(trans, root, path, iref,
1693 refs_to_add, extent_op);
1694 } else if (ret == -ENOENT) {
1695 ret = setup_inline_extent_backref(trans, root, path, iref,
1696 parent, root_objectid,
1697 owner, offset, refs_to_add,
1703 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1704 struct btrfs_root *root,
1705 struct btrfs_path *path,
1706 u64 bytenr, u64 parent, u64 root_objectid,
1707 u64 owner, u64 offset, int refs_to_add)
1710 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1711 BUG_ON(refs_to_add != 1);
1712 ret = insert_tree_block_ref(trans, root, path, bytenr,
1713 parent, root_objectid);
1715 ret = insert_extent_data_ref(trans, root, path, bytenr,
1716 parent, root_objectid,
1717 owner, offset, refs_to_add);
1722 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1723 struct btrfs_root *root,
1724 struct btrfs_path *path,
1725 struct btrfs_extent_inline_ref *iref,
1726 int refs_to_drop, int is_data)
1730 BUG_ON(!is_data && refs_to_drop != 1);
1732 ret = update_inline_extent_backref(trans, root, path, iref,
1733 -refs_to_drop, NULL);
1734 } else if (is_data) {
1735 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1737 ret = btrfs_del_item(trans, root, path);
1742 static void btrfs_issue_discard(struct block_device *bdev,
1745 blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL,
1746 BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER);
1749 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1753 u64 map_length = num_bytes;
1754 struct btrfs_multi_bio *multi = NULL;
1756 if (!btrfs_test_opt(root, DISCARD))
1759 /* Tell the block device(s) that the sectors can be discarded */
1760 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
1761 bytenr, &map_length, &multi, 0);
1763 struct btrfs_bio_stripe *stripe = multi->stripes;
1766 if (map_length > num_bytes)
1767 map_length = num_bytes;
1769 for (i = 0; i < multi->num_stripes; i++, stripe++) {
1770 btrfs_issue_discard(stripe->dev->bdev,
1780 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1781 struct btrfs_root *root,
1782 u64 bytenr, u64 num_bytes, u64 parent,
1783 u64 root_objectid, u64 owner, u64 offset)
1786 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
1787 root_objectid == BTRFS_TREE_LOG_OBJECTID);
1789 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1790 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
1791 parent, root_objectid, (int)owner,
1792 BTRFS_ADD_DELAYED_REF, NULL);
1794 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
1795 parent, root_objectid, owner, offset,
1796 BTRFS_ADD_DELAYED_REF, NULL);
1801 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1802 struct btrfs_root *root,
1803 u64 bytenr, u64 num_bytes,
1804 u64 parent, u64 root_objectid,
1805 u64 owner, u64 offset, int refs_to_add,
1806 struct btrfs_delayed_extent_op *extent_op)
1808 struct btrfs_path *path;
1809 struct extent_buffer *leaf;
1810 struct btrfs_extent_item *item;
1815 path = btrfs_alloc_path();
1820 path->leave_spinning = 1;
1821 /* this will setup the path even if it fails to insert the back ref */
1822 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1823 path, bytenr, num_bytes, parent,
1824 root_objectid, owner, offset,
1825 refs_to_add, extent_op);
1829 if (ret != -EAGAIN) {
1834 leaf = path->nodes[0];
1835 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1836 refs = btrfs_extent_refs(leaf, item);
1837 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1839 __run_delayed_extent_op(extent_op, leaf, item);
1841 btrfs_mark_buffer_dirty(leaf);
1842 btrfs_release_path(root->fs_info->extent_root, path);
1845 path->leave_spinning = 1;
1847 /* now insert the actual backref */
1848 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1849 path, bytenr, parent, root_objectid,
1850 owner, offset, refs_to_add);
1853 btrfs_free_path(path);
1857 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1858 struct btrfs_root *root,
1859 struct btrfs_delayed_ref_node *node,
1860 struct btrfs_delayed_extent_op *extent_op,
1861 int insert_reserved)
1864 struct btrfs_delayed_data_ref *ref;
1865 struct btrfs_key ins;
1870 ins.objectid = node->bytenr;
1871 ins.offset = node->num_bytes;
1872 ins.type = BTRFS_EXTENT_ITEM_KEY;
1874 ref = btrfs_delayed_node_to_data_ref(node);
1875 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1876 parent = ref->parent;
1878 ref_root = ref->root;
1880 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1882 BUG_ON(extent_op->update_key);
1883 flags |= extent_op->flags_to_set;
1885 ret = alloc_reserved_file_extent(trans, root,
1886 parent, ref_root, flags,
1887 ref->objectid, ref->offset,
1888 &ins, node->ref_mod);
1889 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1890 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1891 node->num_bytes, parent,
1892 ref_root, ref->objectid,
1893 ref->offset, node->ref_mod,
1895 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1896 ret = __btrfs_free_extent(trans, root, node->bytenr,
1897 node->num_bytes, parent,
1898 ref_root, ref->objectid,
1899 ref->offset, node->ref_mod,
1907 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1908 struct extent_buffer *leaf,
1909 struct btrfs_extent_item *ei)
1911 u64 flags = btrfs_extent_flags(leaf, ei);
1912 if (extent_op->update_flags) {
1913 flags |= extent_op->flags_to_set;
1914 btrfs_set_extent_flags(leaf, ei, flags);
1917 if (extent_op->update_key) {
1918 struct btrfs_tree_block_info *bi;
1919 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
1920 bi = (struct btrfs_tree_block_info *)(ei + 1);
1921 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
1925 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
1926 struct btrfs_root *root,
1927 struct btrfs_delayed_ref_node *node,
1928 struct btrfs_delayed_extent_op *extent_op)
1930 struct btrfs_key key;
1931 struct btrfs_path *path;
1932 struct btrfs_extent_item *ei;
1933 struct extent_buffer *leaf;
1938 path = btrfs_alloc_path();
1942 key.objectid = node->bytenr;
1943 key.type = BTRFS_EXTENT_ITEM_KEY;
1944 key.offset = node->num_bytes;
1947 path->leave_spinning = 1;
1948 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
1959 leaf = path->nodes[0];
1960 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1961 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1962 if (item_size < sizeof(*ei)) {
1963 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
1969 leaf = path->nodes[0];
1970 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1973 BUG_ON(item_size < sizeof(*ei));
1974 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1975 __run_delayed_extent_op(extent_op, leaf, ei);
1977 btrfs_mark_buffer_dirty(leaf);
1979 btrfs_free_path(path);
1983 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
1984 struct btrfs_root *root,
1985 struct btrfs_delayed_ref_node *node,
1986 struct btrfs_delayed_extent_op *extent_op,
1987 int insert_reserved)
1990 struct btrfs_delayed_tree_ref *ref;
1991 struct btrfs_key ins;
1995 ins.objectid = node->bytenr;
1996 ins.offset = node->num_bytes;
1997 ins.type = BTRFS_EXTENT_ITEM_KEY;
1999 ref = btrfs_delayed_node_to_tree_ref(node);
2000 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2001 parent = ref->parent;
2003 ref_root = ref->root;
2005 BUG_ON(node->ref_mod != 1);
2006 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2007 BUG_ON(!extent_op || !extent_op->update_flags ||
2008 !extent_op->update_key);
2009 ret = alloc_reserved_tree_block(trans, root,
2011 extent_op->flags_to_set,
2014 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2015 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
2016 node->num_bytes, parent, ref_root,
2017 ref->level, 0, 1, extent_op);
2018 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2019 ret = __btrfs_free_extent(trans, root, node->bytenr,
2020 node->num_bytes, parent, ref_root,
2021 ref->level, 0, 1, extent_op);
2028 /* helper function to actually process a single delayed ref entry */
2029 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2030 struct btrfs_root *root,
2031 struct btrfs_delayed_ref_node *node,
2032 struct btrfs_delayed_extent_op *extent_op,
2033 int insert_reserved)
2036 if (btrfs_delayed_ref_is_head(node)) {
2037 struct btrfs_delayed_ref_head *head;
2039 * we've hit the end of the chain and we were supposed
2040 * to insert this extent into the tree. But, it got
2041 * deleted before we ever needed to insert it, so all
2042 * we have to do is clean up the accounting
2045 head = btrfs_delayed_node_to_head(node);
2046 if (insert_reserved) {
2047 btrfs_pin_extent(root, node->bytenr,
2048 node->num_bytes, 1);
2049 if (head->is_data) {
2050 ret = btrfs_del_csums(trans, root,
2056 mutex_unlock(&head->mutex);
2060 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2061 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2062 ret = run_delayed_tree_ref(trans, root, node, extent_op,
2064 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2065 node->type == BTRFS_SHARED_DATA_REF_KEY)
2066 ret = run_delayed_data_ref(trans, root, node, extent_op,
2073 static noinline struct btrfs_delayed_ref_node *
2074 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2076 struct rb_node *node;
2077 struct btrfs_delayed_ref_node *ref;
2078 int action = BTRFS_ADD_DELAYED_REF;
2081 * select delayed ref of type BTRFS_ADD_DELAYED_REF first.
2082 * this prevents ref count from going down to zero when
2083 * there still are pending delayed ref.
2085 node = rb_prev(&head->node.rb_node);
2089 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2091 if (ref->bytenr != head->node.bytenr)
2093 if (ref->action == action)
2095 node = rb_prev(node);
2097 if (action == BTRFS_ADD_DELAYED_REF) {
2098 action = BTRFS_DROP_DELAYED_REF;
2104 static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
2105 struct btrfs_root *root,
2106 struct list_head *cluster)
2108 struct btrfs_delayed_ref_root *delayed_refs;
2109 struct btrfs_delayed_ref_node *ref;
2110 struct btrfs_delayed_ref_head *locked_ref = NULL;
2111 struct btrfs_delayed_extent_op *extent_op;
2114 int must_insert_reserved = 0;
2116 delayed_refs = &trans->transaction->delayed_refs;
2119 /* pick a new head ref from the cluster list */
2120 if (list_empty(cluster))
2123 locked_ref = list_entry(cluster->next,
2124 struct btrfs_delayed_ref_head, cluster);
2126 /* grab the lock that says we are going to process
2127 * all the refs for this head */
2128 ret = btrfs_delayed_ref_lock(trans, locked_ref);
2131 * we may have dropped the spin lock to get the head
2132 * mutex lock, and that might have given someone else
2133 * time to free the head. If that's true, it has been
2134 * removed from our list and we can move on.
2136 if (ret == -EAGAIN) {
2144 * record the must insert reserved flag before we
2145 * drop the spin lock.
2147 must_insert_reserved = locked_ref->must_insert_reserved;
2148 locked_ref->must_insert_reserved = 0;
2150 extent_op = locked_ref->extent_op;
2151 locked_ref->extent_op = NULL;
2154 * locked_ref is the head node, so we have to go one
2155 * node back for any delayed ref updates
2157 ref = select_delayed_ref(locked_ref);
2159 /* All delayed refs have been processed, Go ahead
2160 * and send the head node to run_one_delayed_ref,
2161 * so that any accounting fixes can happen
2163 ref = &locked_ref->node;
2165 if (extent_op && must_insert_reserved) {
2171 spin_unlock(&delayed_refs->lock);
2173 ret = run_delayed_extent_op(trans, root,
2179 spin_lock(&delayed_refs->lock);
2183 list_del_init(&locked_ref->cluster);
2188 rb_erase(&ref->rb_node, &delayed_refs->root);
2189 delayed_refs->num_entries--;
2191 spin_unlock(&delayed_refs->lock);
2193 ret = run_one_delayed_ref(trans, root, ref, extent_op,
2194 must_insert_reserved);
2197 btrfs_put_delayed_ref(ref);
2202 spin_lock(&delayed_refs->lock);
2208 * this starts processing the delayed reference count updates and
2209 * extent insertions we have queued up so far. count can be
2210 * 0, which means to process everything in the tree at the start
2211 * of the run (but not newly added entries), or it can be some target
2212 * number you'd like to process.
2214 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2215 struct btrfs_root *root, unsigned long count)
2217 struct rb_node *node;
2218 struct btrfs_delayed_ref_root *delayed_refs;
2219 struct btrfs_delayed_ref_node *ref;
2220 struct list_head cluster;
2222 int run_all = count == (unsigned long)-1;
2225 if (root == root->fs_info->extent_root)
2226 root = root->fs_info->tree_root;
2228 delayed_refs = &trans->transaction->delayed_refs;
2229 INIT_LIST_HEAD(&cluster);
2231 spin_lock(&delayed_refs->lock);
2233 count = delayed_refs->num_entries * 2;
2237 if (!(run_all || run_most) &&
2238 delayed_refs->num_heads_ready < 64)
2242 * go find something we can process in the rbtree. We start at
2243 * the beginning of the tree, and then build a cluster
2244 * of refs to process starting at the first one we are able to
2247 ret = btrfs_find_ref_cluster(trans, &cluster,
2248 delayed_refs->run_delayed_start);
2252 ret = run_clustered_refs(trans, root, &cluster);
2255 count -= min_t(unsigned long, ret, count);
2262 node = rb_first(&delayed_refs->root);
2265 count = (unsigned long)-1;
2268 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2270 if (btrfs_delayed_ref_is_head(ref)) {
2271 struct btrfs_delayed_ref_head *head;
2273 head = btrfs_delayed_node_to_head(ref);
2274 atomic_inc(&ref->refs);
2276 spin_unlock(&delayed_refs->lock);
2277 mutex_lock(&head->mutex);
2278 mutex_unlock(&head->mutex);
2280 btrfs_put_delayed_ref(ref);
2284 node = rb_next(node);
2286 spin_unlock(&delayed_refs->lock);
2287 schedule_timeout(1);
2291 spin_unlock(&delayed_refs->lock);
2295 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2296 struct btrfs_root *root,
2297 u64 bytenr, u64 num_bytes, u64 flags,
2300 struct btrfs_delayed_extent_op *extent_op;
2303 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2307 extent_op->flags_to_set = flags;
2308 extent_op->update_flags = 1;
2309 extent_op->update_key = 0;
2310 extent_op->is_data = is_data ? 1 : 0;
2312 ret = btrfs_add_delayed_extent_op(trans, bytenr, num_bytes, extent_op);
2318 static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
2319 struct btrfs_root *root,
2320 struct btrfs_path *path,
2321 u64 objectid, u64 offset, u64 bytenr)
2323 struct btrfs_delayed_ref_head *head;
2324 struct btrfs_delayed_ref_node *ref;
2325 struct btrfs_delayed_data_ref *data_ref;
2326 struct btrfs_delayed_ref_root *delayed_refs;
2327 struct rb_node *node;
2331 delayed_refs = &trans->transaction->delayed_refs;
2332 spin_lock(&delayed_refs->lock);
2333 head = btrfs_find_delayed_ref_head(trans, bytenr);
2337 if (!mutex_trylock(&head->mutex)) {
2338 atomic_inc(&head->node.refs);
2339 spin_unlock(&delayed_refs->lock);
2341 btrfs_release_path(root->fs_info->extent_root, path);
2343 mutex_lock(&head->mutex);
2344 mutex_unlock(&head->mutex);
2345 btrfs_put_delayed_ref(&head->node);
2349 node = rb_prev(&head->node.rb_node);
2353 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2355 if (ref->bytenr != bytenr)
2359 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
2362 data_ref = btrfs_delayed_node_to_data_ref(ref);
2364 node = rb_prev(node);
2366 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2367 if (ref->bytenr == bytenr)
2371 if (data_ref->root != root->root_key.objectid ||
2372 data_ref->objectid != objectid || data_ref->offset != offset)
2377 mutex_unlock(&head->mutex);
2379 spin_unlock(&delayed_refs->lock);
2383 static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2384 struct btrfs_root *root,
2385 struct btrfs_path *path,
2386 u64 objectid, u64 offset, u64 bytenr)
2388 struct btrfs_root *extent_root = root->fs_info->extent_root;
2389 struct extent_buffer *leaf;
2390 struct btrfs_extent_data_ref *ref;
2391 struct btrfs_extent_inline_ref *iref;
2392 struct btrfs_extent_item *ei;
2393 struct btrfs_key key;
2397 key.objectid = bytenr;
2398 key.offset = (u64)-1;
2399 key.type = BTRFS_EXTENT_ITEM_KEY;
2401 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2407 if (path->slots[0] == 0)
2411 leaf = path->nodes[0];
2412 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2414 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2418 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2419 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2420 if (item_size < sizeof(*ei)) {
2421 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
2425 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2427 if (item_size != sizeof(*ei) +
2428 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2431 if (btrfs_extent_generation(leaf, ei) <=
2432 btrfs_root_last_snapshot(&root->root_item))
2435 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2436 if (btrfs_extent_inline_ref_type(leaf, iref) !=
2437 BTRFS_EXTENT_DATA_REF_KEY)
2440 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2441 if (btrfs_extent_refs(leaf, ei) !=
2442 btrfs_extent_data_ref_count(leaf, ref) ||
2443 btrfs_extent_data_ref_root(leaf, ref) !=
2444 root->root_key.objectid ||
2445 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2446 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2454 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
2455 struct btrfs_root *root,
2456 u64 objectid, u64 offset, u64 bytenr)
2458 struct btrfs_path *path;
2462 path = btrfs_alloc_path();
2467 ret = check_committed_ref(trans, root, path, objectid,
2469 if (ret && ret != -ENOENT)
2472 ret2 = check_delayed_ref(trans, root, path, objectid,
2474 } while (ret2 == -EAGAIN);
2476 if (ret2 && ret2 != -ENOENT) {
2481 if (ret != -ENOENT || ret2 != -ENOENT)
2484 btrfs_free_path(path);
2485 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2491 int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2492 struct extent_buffer *buf, u32 nr_extents)
2494 struct btrfs_key key;
2495 struct btrfs_file_extent_item *fi;
2503 if (!root->ref_cows)
2506 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
2508 root_gen = root->root_key.offset;
2511 root_gen = trans->transid - 1;
2514 level = btrfs_header_level(buf);
2515 nritems = btrfs_header_nritems(buf);
2518 struct btrfs_leaf_ref *ref;
2519 struct btrfs_extent_info *info;
2521 ref = btrfs_alloc_leaf_ref(root, nr_extents);
2527 ref->root_gen = root_gen;
2528 ref->bytenr = buf->start;
2529 ref->owner = btrfs_header_owner(buf);
2530 ref->generation = btrfs_header_generation(buf);
2531 ref->nritems = nr_extents;
2532 info = ref->extents;
2534 for (i = 0; nr_extents > 0 && i < nritems; i++) {
2536 btrfs_item_key_to_cpu(buf, &key, i);
2537 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2539 fi = btrfs_item_ptr(buf, i,
2540 struct btrfs_file_extent_item);
2541 if (btrfs_file_extent_type(buf, fi) ==
2542 BTRFS_FILE_EXTENT_INLINE)
2544 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2545 if (disk_bytenr == 0)
2548 info->bytenr = disk_bytenr;
2550 btrfs_file_extent_disk_num_bytes(buf, fi);
2551 info->objectid = key.objectid;
2552 info->offset = key.offset;
2556 ret = btrfs_add_leaf_ref(root, ref, shared);
2557 if (ret == -EEXIST && shared) {
2558 struct btrfs_leaf_ref *old;
2559 old = btrfs_lookup_leaf_ref(root, ref->bytenr);
2561 btrfs_remove_leaf_ref(root, old);
2562 btrfs_free_leaf_ref(root, old);
2563 ret = btrfs_add_leaf_ref(root, ref, shared);
2566 btrfs_free_leaf_ref(root, ref);
2572 /* when a block goes through cow, we update the reference counts of
2573 * everything that block points to. The internal pointers of the block
2574 * can be in just about any order, and it is likely to have clusters of
2575 * things that are close together and clusters of things that are not.
2577 * To help reduce the seeks that come with updating all of these reference
2578 * counts, sort them by byte number before actual updates are done.
2580 * struct refsort is used to match byte number to slot in the btree block.
2581 * we sort based on the byte number and then use the slot to actually
2584 * struct refsort is smaller than strcut btrfs_item and smaller than
2585 * struct btrfs_key_ptr. Since we're currently limited to the page size
2586 * for a btree block, there's no way for a kmalloc of refsorts for a
2587 * single node to be bigger than a page.
2595 * for passing into sort()
2597 static int refsort_cmp(const void *a_void, const void *b_void)
2599 const struct refsort *a = a_void;
2600 const struct refsort *b = b_void;
2602 if (a->bytenr < b->bytenr)
2604 if (a->bytenr > b->bytenr)
2610 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2611 struct btrfs_root *root,
2612 struct extent_buffer *buf,
2613 int full_backref, int inc)
2620 struct btrfs_key key;
2621 struct btrfs_file_extent_item *fi;
2625 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
2626 u64, u64, u64, u64, u64, u64);
2628 ref_root = btrfs_header_owner(buf);
2629 nritems = btrfs_header_nritems(buf);
2630 level = btrfs_header_level(buf);
2632 if (!root->ref_cows && level == 0)
2636 process_func = btrfs_inc_extent_ref;
2638 process_func = btrfs_free_extent;
2641 parent = buf->start;
2645 for (i = 0; i < nritems; i++) {
2647 btrfs_item_key_to_cpu(buf, &key, i);
2648 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2650 fi = btrfs_item_ptr(buf, i,
2651 struct btrfs_file_extent_item);
2652 if (btrfs_file_extent_type(buf, fi) ==
2653 BTRFS_FILE_EXTENT_INLINE)
2655 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2659 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2660 key.offset -= btrfs_file_extent_offset(buf, fi);
2661 ret = process_func(trans, root, bytenr, num_bytes,
2662 parent, ref_root, key.objectid,
2667 bytenr = btrfs_node_blockptr(buf, i);
2668 num_bytes = btrfs_level_size(root, level - 1);
2669 ret = process_func(trans, root, bytenr, num_bytes,
2670 parent, ref_root, level - 1, 0);
2681 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2682 struct extent_buffer *buf, int full_backref)
2684 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
2687 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2688 struct extent_buffer *buf, int full_backref)
2690 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
2693 static int write_one_cache_group(struct btrfs_trans_handle *trans,
2694 struct btrfs_root *root,
2695 struct btrfs_path *path,
2696 struct btrfs_block_group_cache *cache)
2699 struct btrfs_root *extent_root = root->fs_info->extent_root;
2701 struct extent_buffer *leaf;
2703 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
2708 leaf = path->nodes[0];
2709 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2710 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
2711 btrfs_mark_buffer_dirty(leaf);
2712 btrfs_release_path(extent_root, path);
2720 static struct btrfs_block_group_cache *
2721 next_block_group(struct btrfs_root *root,
2722 struct btrfs_block_group_cache *cache)
2724 struct rb_node *node;
2725 spin_lock(&root->fs_info->block_group_cache_lock);
2726 node = rb_next(&cache->cache_node);
2727 btrfs_put_block_group(cache);
2729 cache = rb_entry(node, struct btrfs_block_group_cache,
2731 btrfs_get_block_group(cache);
2734 spin_unlock(&root->fs_info->block_group_cache_lock);
2738 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
2739 struct btrfs_trans_handle *trans,
2740 struct btrfs_path *path)
2742 struct btrfs_root *root = block_group->fs_info->tree_root;
2743 struct inode *inode = NULL;
2750 * If this block group is smaller than 100 megs don't bother caching the
2753 if (block_group->key.offset < (100 * 1024 * 1024)) {
2754 spin_lock(&block_group->lock);
2755 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
2756 spin_unlock(&block_group->lock);
2761 inode = lookup_free_space_inode(root, block_group, path);
2762 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
2763 ret = PTR_ERR(inode);
2764 btrfs_release_path(root, path);
2768 if (IS_ERR(inode)) {
2772 if (block_group->ro)
2775 ret = create_free_space_inode(root, trans, block_group, path);
2782 * We want to set the generation to 0, that way if anything goes wrong
2783 * from here on out we know not to trust this cache when we load up next
2786 BTRFS_I(inode)->generation = 0;
2787 ret = btrfs_update_inode(trans, root, inode);
2790 if (i_size_read(inode) > 0) {
2791 ret = btrfs_truncate_free_space_cache(root, trans, path,
2797 spin_lock(&block_group->lock);
2798 if (block_group->cached != BTRFS_CACHE_FINISHED) {
2799 spin_unlock(&block_group->lock);
2802 spin_unlock(&block_group->lock);
2804 num_pages = (int)div64_u64(block_group->key.offset, 1024 * 1024 * 1024);
2809 * Just to make absolutely sure we have enough space, we're going to
2810 * preallocate 12 pages worth of space for each block group. In
2811 * practice we ought to use at most 8, but we need extra space so we can
2812 * add our header and have a terminator between the extents and the
2816 num_pages *= PAGE_CACHE_SIZE;
2818 ret = btrfs_check_data_free_space(inode, num_pages);
2822 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
2823 num_pages, num_pages,
2825 btrfs_free_reserved_data_space(inode, num_pages);
2829 btrfs_release_path(root, path);
2831 spin_lock(&block_group->lock);
2833 block_group->disk_cache_state = BTRFS_DC_ERROR;
2835 block_group->disk_cache_state = BTRFS_DC_SETUP;
2836 spin_unlock(&block_group->lock);
2841 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
2842 struct btrfs_root *root)
2844 struct btrfs_block_group_cache *cache;
2846 struct btrfs_path *path;
2849 path = btrfs_alloc_path();
2855 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2857 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
2859 cache = next_block_group(root, cache);
2867 err = cache_save_setup(cache, trans, path);
2868 last = cache->key.objectid + cache->key.offset;
2869 btrfs_put_block_group(cache);
2874 err = btrfs_run_delayed_refs(trans, root,
2879 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2881 if (cache->disk_cache_state == BTRFS_DC_CLEAR) {
2882 btrfs_put_block_group(cache);
2888 cache = next_block_group(root, cache);
2897 if (cache->disk_cache_state == BTRFS_DC_SETUP)
2898 cache->disk_cache_state = BTRFS_DC_NEED_WRITE;
2900 last = cache->key.objectid + cache->key.offset;
2902 err = write_one_cache_group(trans, root, path, cache);
2904 btrfs_put_block_group(cache);
2909 * I don't think this is needed since we're just marking our
2910 * preallocated extent as written, but just in case it can't
2914 err = btrfs_run_delayed_refs(trans, root,
2919 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2922 * Really this shouldn't happen, but it could if we
2923 * couldn't write the entire preallocated extent and
2924 * splitting the extent resulted in a new block.
2927 btrfs_put_block_group(cache);
2930 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2932 cache = next_block_group(root, cache);
2941 btrfs_write_out_cache(root, trans, cache, path);
2944 * If we didn't have an error then the cache state is still
2945 * NEED_WRITE, so we can set it to WRITTEN.
2947 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2948 cache->disk_cache_state = BTRFS_DC_WRITTEN;
2949 last = cache->key.objectid + cache->key.offset;
2950 btrfs_put_block_group(cache);
2953 btrfs_free_path(path);
2957 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
2959 struct btrfs_block_group_cache *block_group;
2962 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
2963 if (!block_group || block_group->ro)
2966 btrfs_put_block_group(block_group);
2970 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
2971 u64 total_bytes, u64 bytes_used,
2972 struct btrfs_space_info **space_info)
2974 struct btrfs_space_info *found;
2978 if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
2979 BTRFS_BLOCK_GROUP_RAID10))
2984 found = __find_space_info(info, flags);
2986 spin_lock(&found->lock);
2987 found->total_bytes += total_bytes;
2988 found->disk_total += total_bytes * factor;
2989 found->bytes_used += bytes_used;
2990 found->disk_used += bytes_used * factor;
2992 spin_unlock(&found->lock);
2993 *space_info = found;
2996 found = kzalloc(sizeof(*found), GFP_NOFS);
3000 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
3001 INIT_LIST_HEAD(&found->block_groups[i]);
3002 init_rwsem(&found->groups_sem);
3003 spin_lock_init(&found->lock);
3004 found->flags = flags & (BTRFS_BLOCK_GROUP_DATA |
3005 BTRFS_BLOCK_GROUP_SYSTEM |
3006 BTRFS_BLOCK_GROUP_METADATA);
3007 found->total_bytes = total_bytes;
3008 found->disk_total = total_bytes * factor;
3009 found->bytes_used = bytes_used;
3010 found->disk_used = bytes_used * factor;
3011 found->bytes_pinned = 0;
3012 found->bytes_reserved = 0;
3013 found->bytes_readonly = 0;
3014 found->bytes_may_use = 0;
3016 found->force_alloc = 0;
3017 *space_info = found;
3018 list_add_rcu(&found->list, &info->space_info);
3019 atomic_set(&found->caching_threads, 0);
3023 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
3025 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
3026 BTRFS_BLOCK_GROUP_RAID1 |
3027 BTRFS_BLOCK_GROUP_RAID10 |
3028 BTRFS_BLOCK_GROUP_DUP);
3030 if (flags & BTRFS_BLOCK_GROUP_DATA)
3031 fs_info->avail_data_alloc_bits |= extra_flags;
3032 if (flags & BTRFS_BLOCK_GROUP_METADATA)
3033 fs_info->avail_metadata_alloc_bits |= extra_flags;
3034 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3035 fs_info->avail_system_alloc_bits |= extra_flags;
3039 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
3041 u64 num_devices = root->fs_info->fs_devices->rw_devices;
3043 if (num_devices == 1)
3044 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
3045 if (num_devices < 4)
3046 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
3048 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
3049 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
3050 BTRFS_BLOCK_GROUP_RAID10))) {
3051 flags &= ~BTRFS_BLOCK_GROUP_DUP;
3054 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
3055 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
3056 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
3059 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
3060 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
3061 (flags & BTRFS_BLOCK_GROUP_RAID10) |
3062 (flags & BTRFS_BLOCK_GROUP_DUP)))
3063 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
3067 static u64 get_alloc_profile(struct btrfs_root *root, u64 flags)
3069 if (flags & BTRFS_BLOCK_GROUP_DATA)
3070 flags |= root->fs_info->avail_data_alloc_bits &
3071 root->fs_info->data_alloc_profile;
3072 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3073 flags |= root->fs_info->avail_system_alloc_bits &
3074 root->fs_info->system_alloc_profile;
3075 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
3076 flags |= root->fs_info->avail_metadata_alloc_bits &
3077 root->fs_info->metadata_alloc_profile;
3078 return btrfs_reduce_alloc_profile(root, flags);
3081 static u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
3086 flags = BTRFS_BLOCK_GROUP_DATA;
3087 else if (root == root->fs_info->chunk_root)
3088 flags = BTRFS_BLOCK_GROUP_SYSTEM;
3090 flags = BTRFS_BLOCK_GROUP_METADATA;
3092 return get_alloc_profile(root, flags);
3095 void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
3097 BTRFS_I(inode)->space_info = __find_space_info(root->fs_info,
3098 BTRFS_BLOCK_GROUP_DATA);
3102 * This will check the space that the inode allocates from to make sure we have
3103 * enough space for bytes.
3105 int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
3107 struct btrfs_space_info *data_sinfo;
3108 struct btrfs_root *root = BTRFS_I(inode)->root;
3110 int ret = 0, committed = 0, alloc_chunk = 1;
3112 /* make sure bytes are sectorsize aligned */
3113 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3115 if (root == root->fs_info->tree_root) {
3120 data_sinfo = BTRFS_I(inode)->space_info;
3125 /* make sure we have enough space to handle the data first */
3126 spin_lock(&data_sinfo->lock);
3127 used = data_sinfo->bytes_used + data_sinfo->bytes_reserved +
3128 data_sinfo->bytes_pinned + data_sinfo->bytes_readonly +
3129 data_sinfo->bytes_may_use;
3131 if (used + bytes > data_sinfo->total_bytes) {
3132 struct btrfs_trans_handle *trans;
3135 * if we don't have enough free bytes in this space then we need
3136 * to alloc a new chunk.
3138 if (!data_sinfo->full && alloc_chunk) {
3141 data_sinfo->force_alloc = 1;
3142 spin_unlock(&data_sinfo->lock);
3144 alloc_target = btrfs_get_alloc_profile(root, 1);
3145 trans = btrfs_join_transaction(root, 1);
3147 return PTR_ERR(trans);
3149 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3150 bytes + 2 * 1024 * 1024,
3152 btrfs_end_transaction(trans, root);
3157 btrfs_set_inode_space_info(root, inode);
3158 data_sinfo = BTRFS_I(inode)->space_info;
3162 spin_unlock(&data_sinfo->lock);
3164 /* commit the current transaction and try again */
3165 if (!committed && !root->fs_info->open_ioctl_trans) {
3167 trans = btrfs_join_transaction(root, 1);
3169 return PTR_ERR(trans);
3170 ret = btrfs_commit_transaction(trans, root);
3176 #if 0 /* I hope we never need this code again, just in case */
3177 printk(KERN_ERR "no space left, need %llu, %llu bytes_used, "
3178 "%llu bytes_reserved, " "%llu bytes_pinned, "
3179 "%llu bytes_readonly, %llu may use %llu total\n",
3180 (unsigned long long)bytes,
3181 (unsigned long long)data_sinfo->bytes_used,
3182 (unsigned long long)data_sinfo->bytes_reserved,
3183 (unsigned long long)data_sinfo->bytes_pinned,
3184 (unsigned long long)data_sinfo->bytes_readonly,
3185 (unsigned long long)data_sinfo->bytes_may_use,
3186 (unsigned long long)data_sinfo->total_bytes);
3190 data_sinfo->bytes_may_use += bytes;
3191 BTRFS_I(inode)->reserved_bytes += bytes;
3192 spin_unlock(&data_sinfo->lock);
3198 * called when we are clearing an delalloc extent from the
3199 * inode's io_tree or there was an error for whatever reason
3200 * after calling btrfs_check_data_free_space
3202 void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes)
3204 struct btrfs_root *root = BTRFS_I(inode)->root;
3205 struct btrfs_space_info *data_sinfo;
3207 /* make sure bytes are sectorsize aligned */
3208 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3210 data_sinfo = BTRFS_I(inode)->space_info;
3211 spin_lock(&data_sinfo->lock);
3212 data_sinfo->bytes_may_use -= bytes;
3213 BTRFS_I(inode)->reserved_bytes -= bytes;
3214 spin_unlock(&data_sinfo->lock);
3217 static void force_metadata_allocation(struct btrfs_fs_info *info)
3219 struct list_head *head = &info->space_info;
3220 struct btrfs_space_info *found;
3223 list_for_each_entry_rcu(found, head, list) {
3224 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
3225 found->force_alloc = 1;
3230 static int should_alloc_chunk(struct btrfs_root *root,
3231 struct btrfs_space_info *sinfo, u64 alloc_bytes)
3233 u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
3236 if (sinfo->bytes_used + sinfo->bytes_reserved +
3237 alloc_bytes + 256 * 1024 * 1024 < num_bytes)
3240 if (sinfo->bytes_used + sinfo->bytes_reserved +
3241 alloc_bytes < div_factor(num_bytes, 8))
3244 thresh = btrfs_super_total_bytes(&root->fs_info->super_copy);
3245 thresh = max_t(u64, 256 * 1024 * 1024, div_factor_fine(thresh, 5));
3247 if (num_bytes > thresh && sinfo->bytes_used < div_factor(num_bytes, 3))
3253 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
3254 struct btrfs_root *extent_root, u64 alloc_bytes,
3255 u64 flags, int force)
3257 struct btrfs_space_info *space_info;
3258 struct btrfs_fs_info *fs_info = extent_root->fs_info;
3261 mutex_lock(&fs_info->chunk_mutex);
3263 flags = btrfs_reduce_alloc_profile(extent_root, flags);
3265 space_info = __find_space_info(extent_root->fs_info, flags);
3267 ret = update_space_info(extent_root->fs_info, flags,
3271 BUG_ON(!space_info);
3273 spin_lock(&space_info->lock);
3274 if (space_info->force_alloc)
3276 if (space_info->full) {
3277 spin_unlock(&space_info->lock);
3281 if (!force && !should_alloc_chunk(extent_root, space_info,
3283 spin_unlock(&space_info->lock);
3286 spin_unlock(&space_info->lock);
3289 * If we have mixed data/metadata chunks we want to make sure we keep
3290 * allocating mixed chunks instead of individual chunks.
3292 if (btrfs_mixed_space_info(space_info))
3293 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
3296 * if we're doing a data chunk, go ahead and make sure that
3297 * we keep a reasonable number of metadata chunks allocated in the
3300 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
3301 fs_info->data_chunk_allocations++;
3302 if (!(fs_info->data_chunk_allocations %
3303 fs_info->metadata_ratio))
3304 force_metadata_allocation(fs_info);
3307 ret = btrfs_alloc_chunk(trans, extent_root, flags);
3308 spin_lock(&space_info->lock);
3310 space_info->full = 1;
3313 space_info->force_alloc = 0;
3314 spin_unlock(&space_info->lock);
3316 mutex_unlock(&extent_root->fs_info->chunk_mutex);
3321 * shrink metadata reservation for delalloc
3323 static int shrink_delalloc(struct btrfs_trans_handle *trans,
3324 struct btrfs_root *root, u64 to_reclaim, int sync)
3326 struct btrfs_block_rsv *block_rsv;
3327 struct btrfs_space_info *space_info;
3332 int nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
3334 block_rsv = &root->fs_info->delalloc_block_rsv;
3335 space_info = block_rsv->space_info;
3338 reserved = space_info->bytes_reserved;
3343 max_reclaim = min(reserved, to_reclaim);
3346 /* have the flusher threads jump in and do some IO */
3348 nr_pages = min_t(unsigned long, nr_pages,
3349 root->fs_info->delalloc_bytes >> PAGE_CACHE_SHIFT);
3350 writeback_inodes_sb_nr_if_idle(root->fs_info->sb, nr_pages);
3352 spin_lock(&space_info->lock);
3353 if (reserved > space_info->bytes_reserved)
3354 reclaimed += reserved - space_info->bytes_reserved;
3355 reserved = space_info->bytes_reserved;
3356 spin_unlock(&space_info->lock);
3358 if (reserved == 0 || reclaimed >= max_reclaim)
3361 if (trans && trans->transaction->blocked)
3364 __set_current_state(TASK_INTERRUPTIBLE);
3365 schedule_timeout(pause);
3367 if (pause > HZ / 10)
3371 return reclaimed >= to_reclaim;
3375 * Retries tells us how many times we've called reserve_metadata_bytes. The
3376 * idea is if this is the first call (retries == 0) then we will add to our
3377 * reserved count if we can't make the allocation in order to hold our place
3378 * while we go and try and free up space. That way for retries > 1 we don't try
3379 * and add space, we just check to see if the amount of unused space is >= the
3380 * total space, meaning that our reservation is valid.
3382 * However if we don't intend to retry this reservation, pass -1 as retries so
3383 * that it short circuits this logic.
3385 static int reserve_metadata_bytes(struct btrfs_trans_handle *trans,
3386 struct btrfs_root *root,
3387 struct btrfs_block_rsv *block_rsv,
3388 u64 orig_bytes, int flush)
3390 struct btrfs_space_info *space_info = block_rsv->space_info;
3392 u64 num_bytes = orig_bytes;
3395 bool reserved = false;
3396 bool committed = false;
3403 spin_lock(&space_info->lock);
3404 unused = space_info->bytes_used + space_info->bytes_reserved +
3405 space_info->bytes_pinned + space_info->bytes_readonly +
3406 space_info->bytes_may_use;
3409 * The idea here is that we've not already over-reserved the block group
3410 * then we can go ahead and save our reservation first and then start
3411 * flushing if we need to. Otherwise if we've already overcommitted
3412 * lets start flushing stuff first and then come back and try to make
3415 if (unused <= space_info->total_bytes) {
3416 unused -= space_info->total_bytes;
3417 if (unused >= num_bytes) {
3419 space_info->bytes_reserved += orig_bytes;
3423 * Ok set num_bytes to orig_bytes since we aren't
3424 * overocmmitted, this way we only try and reclaim what
3427 num_bytes = orig_bytes;
3431 * Ok we're over committed, set num_bytes to the overcommitted
3432 * amount plus the amount of bytes that we need for this
3435 num_bytes = unused - space_info->total_bytes +
3436 (orig_bytes * (retries + 1));
3440 * Couldn't make our reservation, save our place so while we're trying
3441 * to reclaim space we can actually use it instead of somebody else
3442 * stealing it from us.
3444 if (ret && !reserved) {
3445 space_info->bytes_reserved += orig_bytes;
3449 spin_unlock(&space_info->lock);
3458 * We do synchronous shrinking since we don't actually unreserve
3459 * metadata until after the IO is completed.
3461 ret = shrink_delalloc(trans, root, num_bytes, 1);
3468 * So if we were overcommitted it's possible that somebody else flushed
3469 * out enough space and we simply didn't have enough space to reclaim,
3470 * so go back around and try again.
3477 spin_lock(&space_info->lock);
3479 * Not enough space to be reclaimed, don't bother committing the
3482 if (space_info->bytes_pinned < orig_bytes)
3484 spin_unlock(&space_info->lock);
3489 if (trans || committed)
3493 trans = btrfs_join_transaction(root, 1);
3496 ret = btrfs_commit_transaction(trans, root);
3505 spin_lock(&space_info->lock);
3506 space_info->bytes_reserved -= orig_bytes;
3507 spin_unlock(&space_info->lock);
3513 static struct btrfs_block_rsv *get_block_rsv(struct btrfs_trans_handle *trans,
3514 struct btrfs_root *root)
3516 struct btrfs_block_rsv *block_rsv;
3518 block_rsv = trans->block_rsv;
3520 block_rsv = root->block_rsv;
3523 block_rsv = &root->fs_info->empty_block_rsv;
3528 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
3532 spin_lock(&block_rsv->lock);
3533 if (block_rsv->reserved >= num_bytes) {
3534 block_rsv->reserved -= num_bytes;
3535 if (block_rsv->reserved < block_rsv->size)
3536 block_rsv->full = 0;
3539 spin_unlock(&block_rsv->lock);
3543 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
3544 u64 num_bytes, int update_size)
3546 spin_lock(&block_rsv->lock);
3547 block_rsv->reserved += num_bytes;
3549 block_rsv->size += num_bytes;
3550 else if (block_rsv->reserved >= block_rsv->size)
3551 block_rsv->full = 1;
3552 spin_unlock(&block_rsv->lock);
3555 void block_rsv_release_bytes(struct btrfs_block_rsv *block_rsv,
3556 struct btrfs_block_rsv *dest, u64 num_bytes)
3558 struct btrfs_space_info *space_info = block_rsv->space_info;
3560 spin_lock(&block_rsv->lock);
3561 if (num_bytes == (u64)-1)
3562 num_bytes = block_rsv->size;
3563 block_rsv->size -= num_bytes;
3564 if (block_rsv->reserved >= block_rsv->size) {
3565 num_bytes = block_rsv->reserved - block_rsv->size;
3566 block_rsv->reserved = block_rsv->size;
3567 block_rsv->full = 1;
3571 spin_unlock(&block_rsv->lock);
3573 if (num_bytes > 0) {
3575 block_rsv_add_bytes(dest, num_bytes, 0);
3577 spin_lock(&space_info->lock);
3578 space_info->bytes_reserved -= num_bytes;
3579 spin_unlock(&space_info->lock);
3584 static int block_rsv_migrate_bytes(struct btrfs_block_rsv *src,
3585 struct btrfs_block_rsv *dst, u64 num_bytes)
3589 ret = block_rsv_use_bytes(src, num_bytes);
3593 block_rsv_add_bytes(dst, num_bytes, 1);
3597 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv)
3599 memset(rsv, 0, sizeof(*rsv));
3600 spin_lock_init(&rsv->lock);
3601 atomic_set(&rsv->usage, 1);
3603 INIT_LIST_HEAD(&rsv->list);
3606 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root)
3608 struct btrfs_block_rsv *block_rsv;
3609 struct btrfs_fs_info *fs_info = root->fs_info;
3612 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
3616 btrfs_init_block_rsv(block_rsv);
3618 alloc_target = btrfs_get_alloc_profile(root, 0);
3619 block_rsv->space_info = __find_space_info(fs_info,
3620 BTRFS_BLOCK_GROUP_METADATA);
3625 void btrfs_free_block_rsv(struct btrfs_root *root,
3626 struct btrfs_block_rsv *rsv)
3628 if (rsv && atomic_dec_and_test(&rsv->usage)) {
3629 btrfs_block_rsv_release(root, rsv, (u64)-1);
3636 * make the block_rsv struct be able to capture freed space.
3637 * the captured space will re-add to the the block_rsv struct
3638 * after transaction commit
3640 void btrfs_add_durable_block_rsv(struct btrfs_fs_info *fs_info,
3641 struct btrfs_block_rsv *block_rsv)
3643 block_rsv->durable = 1;
3644 mutex_lock(&fs_info->durable_block_rsv_mutex);
3645 list_add_tail(&block_rsv->list, &fs_info->durable_block_rsv_list);
3646 mutex_unlock(&fs_info->durable_block_rsv_mutex);
3649 int btrfs_block_rsv_add(struct btrfs_trans_handle *trans,
3650 struct btrfs_root *root,
3651 struct btrfs_block_rsv *block_rsv,
3659 ret = reserve_metadata_bytes(trans, root, block_rsv, num_bytes, 1);
3661 block_rsv_add_bytes(block_rsv, num_bytes, 1);
3668 int btrfs_block_rsv_check(struct btrfs_trans_handle *trans,
3669 struct btrfs_root *root,
3670 struct btrfs_block_rsv *block_rsv,
3671 u64 min_reserved, int min_factor)
3674 int commit_trans = 0;
3680 spin_lock(&block_rsv->lock);
3682 num_bytes = div_factor(block_rsv->size, min_factor);
3683 if (min_reserved > num_bytes)
3684 num_bytes = min_reserved;
3686 if (block_rsv->reserved >= num_bytes) {
3689 num_bytes -= block_rsv->reserved;
3690 if (block_rsv->durable &&
3691 block_rsv->freed[0] + block_rsv->freed[1] >= num_bytes)
3694 spin_unlock(&block_rsv->lock);
3698 if (block_rsv->refill_used) {
3699 ret = reserve_metadata_bytes(trans, root, block_rsv,
3702 block_rsv_add_bytes(block_rsv, num_bytes, 0);
3711 trans = btrfs_join_transaction(root, 1);
3712 BUG_ON(IS_ERR(trans));
3713 ret = btrfs_commit_transaction(trans, root);
3718 printk(KERN_INFO"block_rsv size %llu reserved %llu freed %llu %llu\n",
3719 block_rsv->size, block_rsv->reserved,
3720 block_rsv->freed[0], block_rsv->freed[1]);
3725 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
3726 struct btrfs_block_rsv *dst_rsv,
3729 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3732 void btrfs_block_rsv_release(struct btrfs_root *root,
3733 struct btrfs_block_rsv *block_rsv,
3736 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
3737 if (global_rsv->full || global_rsv == block_rsv ||
3738 block_rsv->space_info != global_rsv->space_info)
3740 block_rsv_release_bytes(block_rsv, global_rsv, num_bytes);
3744 * helper to calculate size of global block reservation.
3745 * the desired value is sum of space used by extent tree,
3746 * checksum tree and root tree
3748 static u64 calc_global_metadata_size(struct btrfs_fs_info *fs_info)
3750 struct btrfs_space_info *sinfo;
3754 int csum_size = btrfs_super_csum_size(&fs_info->super_copy);
3757 * per tree used space accounting can be inaccuracy, so we
3760 spin_lock(&fs_info->extent_root->accounting_lock);
3761 num_bytes = btrfs_root_used(&fs_info->extent_root->root_item);
3762 spin_unlock(&fs_info->extent_root->accounting_lock);
3764 spin_lock(&fs_info->csum_root->accounting_lock);
3765 num_bytes += btrfs_root_used(&fs_info->csum_root->root_item);
3766 spin_unlock(&fs_info->csum_root->accounting_lock);
3768 spin_lock(&fs_info->tree_root->accounting_lock);
3769 num_bytes += btrfs_root_used(&fs_info->tree_root->root_item);
3770 spin_unlock(&fs_info->tree_root->accounting_lock);
3772 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_DATA);
3773 spin_lock(&sinfo->lock);
3774 data_used = sinfo->bytes_used;
3775 spin_unlock(&sinfo->lock);
3777 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3778 spin_lock(&sinfo->lock);
3779 if (sinfo->flags & BTRFS_BLOCK_GROUP_DATA)
3781 meta_used = sinfo->bytes_used;
3782 spin_unlock(&sinfo->lock);
3784 num_bytes = (data_used >> fs_info->sb->s_blocksize_bits) *
3786 num_bytes += div64_u64(data_used + meta_used, 50);
3788 if (num_bytes * 3 > meta_used)
3789 num_bytes = div64_u64(meta_used, 3);
3791 return ALIGN(num_bytes, fs_info->extent_root->leafsize << 10);
3794 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
3796 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3797 struct btrfs_space_info *sinfo = block_rsv->space_info;
3800 num_bytes = calc_global_metadata_size(fs_info);
3802 spin_lock(&block_rsv->lock);
3803 spin_lock(&sinfo->lock);
3805 block_rsv->size = num_bytes;
3807 num_bytes = sinfo->bytes_used + sinfo->bytes_pinned +
3808 sinfo->bytes_reserved + sinfo->bytes_readonly +
3809 sinfo->bytes_may_use;
3811 if (sinfo->total_bytes > num_bytes) {
3812 num_bytes = sinfo->total_bytes - num_bytes;
3813 block_rsv->reserved += num_bytes;
3814 sinfo->bytes_reserved += num_bytes;
3817 if (block_rsv->reserved >= block_rsv->size) {
3818 num_bytes = block_rsv->reserved - block_rsv->size;
3819 sinfo->bytes_reserved -= num_bytes;
3820 block_rsv->reserved = block_rsv->size;
3821 block_rsv->full = 1;
3824 printk(KERN_INFO"global block rsv size %llu reserved %llu\n",
3825 block_rsv->size, block_rsv->reserved);
3827 spin_unlock(&sinfo->lock);
3828 spin_unlock(&block_rsv->lock);
3831 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
3833 struct btrfs_space_info *space_info;
3835 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
3836 fs_info->chunk_block_rsv.space_info = space_info;
3837 fs_info->chunk_block_rsv.priority = 10;
3839 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3840 fs_info->global_block_rsv.space_info = space_info;
3841 fs_info->global_block_rsv.priority = 10;
3842 fs_info->global_block_rsv.refill_used = 1;
3843 fs_info->delalloc_block_rsv.space_info = space_info;
3844 fs_info->trans_block_rsv.space_info = space_info;
3845 fs_info->empty_block_rsv.space_info = space_info;
3846 fs_info->empty_block_rsv.priority = 10;
3848 fs_info->extent_root->block_rsv = &fs_info->global_block_rsv;
3849 fs_info->csum_root->block_rsv = &fs_info->global_block_rsv;
3850 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
3851 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
3852 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
3854 btrfs_add_durable_block_rsv(fs_info, &fs_info->global_block_rsv);
3856 btrfs_add_durable_block_rsv(fs_info, &fs_info->delalloc_block_rsv);
3858 update_global_block_rsv(fs_info);
3861 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
3863 block_rsv_release_bytes(&fs_info->global_block_rsv, NULL, (u64)-1);
3864 WARN_ON(fs_info->delalloc_block_rsv.size > 0);
3865 WARN_ON(fs_info->delalloc_block_rsv.reserved > 0);
3866 WARN_ON(fs_info->trans_block_rsv.size > 0);
3867 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
3868 WARN_ON(fs_info->chunk_block_rsv.size > 0);
3869 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
3872 static u64 calc_trans_metadata_size(struct btrfs_root *root, int num_items)
3874 return (root->leafsize + root->nodesize * (BTRFS_MAX_LEVEL - 1)) *
3878 int btrfs_trans_reserve_metadata(struct btrfs_trans_handle *trans,
3879 struct btrfs_root *root,
3885 if (num_items == 0 || root->fs_info->chunk_root == root)
3888 num_bytes = calc_trans_metadata_size(root, num_items);
3889 ret = btrfs_block_rsv_add(trans, root, &root->fs_info->trans_block_rsv,
3892 trans->bytes_reserved += num_bytes;
3893 trans->block_rsv = &root->fs_info->trans_block_rsv;
3898 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
3899 struct btrfs_root *root)
3901 if (!trans->bytes_reserved)
3904 BUG_ON(trans->block_rsv != &root->fs_info->trans_block_rsv);
3905 btrfs_block_rsv_release(root, trans->block_rsv,
3906 trans->bytes_reserved);
3907 trans->bytes_reserved = 0;
3910 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
3911 struct inode *inode)
3913 struct btrfs_root *root = BTRFS_I(inode)->root;
3914 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3915 struct btrfs_block_rsv *dst_rsv = root->orphan_block_rsv;
3918 * one for deleting orphan item, one for updating inode and
3919 * two for calling btrfs_truncate_inode_items.
3921 * btrfs_truncate_inode_items is a delete operation, it frees
3922 * more space than it uses in most cases. So two units of
3923 * metadata space should be enough for calling it many times.
3924 * If all of the metadata space is used, we can commit
3925 * transaction and use space it freed.
3927 u64 num_bytes = calc_trans_metadata_size(root, 4);
3928 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3931 void btrfs_orphan_release_metadata(struct inode *inode)
3933 struct btrfs_root *root = BTRFS_I(inode)->root;
3934 u64 num_bytes = calc_trans_metadata_size(root, 4);
3935 btrfs_block_rsv_release(root, root->orphan_block_rsv, num_bytes);
3938 int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans,
3939 struct btrfs_pending_snapshot *pending)
3941 struct btrfs_root *root = pending->root;
3942 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3943 struct btrfs_block_rsv *dst_rsv = &pending->block_rsv;
3945 * two for root back/forward refs, two for directory entries
3946 * and one for root of the snapshot.
3948 u64 num_bytes = calc_trans_metadata_size(root, 5);
3949 dst_rsv->space_info = src_rsv->space_info;
3950 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3953 static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes)
3955 return num_bytes >>= 3;
3958 int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
3960 struct btrfs_root *root = BTRFS_I(inode)->root;
3961 struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
3966 if (btrfs_transaction_in_commit(root->fs_info))
3967 schedule_timeout(1);
3969 num_bytes = ALIGN(num_bytes, root->sectorsize);
3971 spin_lock(&BTRFS_I(inode)->accounting_lock);
3972 nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents) + 1;
3973 if (nr_extents > BTRFS_I(inode)->reserved_extents) {
3974 nr_extents -= BTRFS_I(inode)->reserved_extents;
3975 to_reserve = calc_trans_metadata_size(root, nr_extents);
3980 spin_unlock(&BTRFS_I(inode)->accounting_lock);
3982 to_reserve += calc_csum_metadata_size(inode, num_bytes);
3983 ret = reserve_metadata_bytes(NULL, root, block_rsv, to_reserve, 1);
3987 spin_lock(&BTRFS_I(inode)->accounting_lock);
3988 BTRFS_I(inode)->reserved_extents += nr_extents;
3989 atomic_inc(&BTRFS_I(inode)->outstanding_extents);
3990 spin_unlock(&BTRFS_I(inode)->accounting_lock);
3992 block_rsv_add_bytes(block_rsv, to_reserve, 1);
3994 if (block_rsv->size > 512 * 1024 * 1024)
3995 shrink_delalloc(NULL, root, to_reserve, 0);
4000 void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
4002 struct btrfs_root *root = BTRFS_I(inode)->root;
4006 num_bytes = ALIGN(num_bytes, root->sectorsize);
4007 atomic_dec(&BTRFS_I(inode)->outstanding_extents);
4009 spin_lock(&BTRFS_I(inode)->accounting_lock);
4010 nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents);
4011 if (nr_extents < BTRFS_I(inode)->reserved_extents) {
4012 nr_extents = BTRFS_I(inode)->reserved_extents - nr_extents;
4013 BTRFS_I(inode)->reserved_extents -= nr_extents;
4017 spin_unlock(&BTRFS_I(inode)->accounting_lock);
4019 to_free = calc_csum_metadata_size(inode, num_bytes);
4021 to_free += calc_trans_metadata_size(root, nr_extents);
4023 btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
4027 int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes)
4031 ret = btrfs_check_data_free_space(inode, num_bytes);
4035 ret = btrfs_delalloc_reserve_metadata(inode, num_bytes);
4037 btrfs_free_reserved_data_space(inode, num_bytes);
4044 void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes)
4046 btrfs_delalloc_release_metadata(inode, num_bytes);
4047 btrfs_free_reserved_data_space(inode, num_bytes);
4050 static int update_block_group(struct btrfs_trans_handle *trans,
4051 struct btrfs_root *root,
4052 u64 bytenr, u64 num_bytes, int alloc)
4054 struct btrfs_block_group_cache *cache = NULL;
4055 struct btrfs_fs_info *info = root->fs_info;
4056 u64 total = num_bytes;
4061 /* block accounting for super block */
4062 spin_lock(&info->delalloc_lock);
4063 old_val = btrfs_super_bytes_used(&info->super_copy);
4065 old_val += num_bytes;
4067 old_val -= num_bytes;
4068 btrfs_set_super_bytes_used(&info->super_copy, old_val);
4069 spin_unlock(&info->delalloc_lock);
4072 cache = btrfs_lookup_block_group(info, bytenr);
4075 if (cache->flags & (BTRFS_BLOCK_GROUP_DUP |
4076 BTRFS_BLOCK_GROUP_RAID1 |
4077 BTRFS_BLOCK_GROUP_RAID10))
4082 * If this block group has free space cache written out, we
4083 * need to make sure to load it if we are removing space. This
4084 * is because we need the unpinning stage to actually add the
4085 * space back to the block group, otherwise we will leak space.
4087 if (!alloc && cache->cached == BTRFS_CACHE_NO)
4088 cache_block_group(cache, trans, 1);
4090 byte_in_group = bytenr - cache->key.objectid;
4091 WARN_ON(byte_in_group > cache->key.offset);
4093 spin_lock(&cache->space_info->lock);
4094 spin_lock(&cache->lock);
4096 if (btrfs_super_cache_generation(&info->super_copy) != 0 &&
4097 cache->disk_cache_state < BTRFS_DC_CLEAR)
4098 cache->disk_cache_state = BTRFS_DC_CLEAR;
4101 old_val = btrfs_block_group_used(&cache->item);
4102 num_bytes = min(total, cache->key.offset - byte_in_group);
4104 old_val += num_bytes;
4105 btrfs_set_block_group_used(&cache->item, old_val);
4106 cache->reserved -= num_bytes;
4107 cache->space_info->bytes_reserved -= num_bytes;
4108 cache->space_info->bytes_used += num_bytes;
4109 cache->space_info->disk_used += num_bytes * factor;
4110 spin_unlock(&cache->lock);
4111 spin_unlock(&cache->space_info->lock);
4113 old_val -= num_bytes;
4114 btrfs_set_block_group_used(&cache->item, old_val);
4115 cache->pinned += num_bytes;
4116 cache->space_info->bytes_pinned += num_bytes;
4117 cache->space_info->bytes_used -= num_bytes;
4118 cache->space_info->disk_used -= num_bytes * factor;
4119 spin_unlock(&cache->lock);
4120 spin_unlock(&cache->space_info->lock);
4122 set_extent_dirty(info->pinned_extents,
4123 bytenr, bytenr + num_bytes - 1,
4124 GFP_NOFS | __GFP_NOFAIL);
4126 btrfs_put_block_group(cache);
4128 bytenr += num_bytes;
4133 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
4135 struct btrfs_block_group_cache *cache;
4138 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
4142 bytenr = cache->key.objectid;
4143 btrfs_put_block_group(cache);
4148 static int pin_down_extent(struct btrfs_root *root,
4149 struct btrfs_block_group_cache *cache,
4150 u64 bytenr, u64 num_bytes, int reserved)
4152 spin_lock(&cache->space_info->lock);
4153 spin_lock(&cache->lock);
4154 cache->pinned += num_bytes;
4155 cache->space_info->bytes_pinned += num_bytes;
4157 cache->reserved -= num_bytes;
4158 cache->space_info->bytes_reserved -= num_bytes;
4160 spin_unlock(&cache->lock);
4161 spin_unlock(&cache->space_info->lock);
4163 set_extent_dirty(root->fs_info->pinned_extents, bytenr,
4164 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
4169 * this function must be called within transaction
4171 int btrfs_pin_extent(struct btrfs_root *root,
4172 u64 bytenr, u64 num_bytes, int reserved)
4174 struct btrfs_block_group_cache *cache;
4176 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
4179 pin_down_extent(root, cache, bytenr, num_bytes, reserved);
4181 btrfs_put_block_group(cache);
4186 * update size of reserved extents. this function may return -EAGAIN
4187 * if 'reserve' is true or 'sinfo' is false.
4189 static int update_reserved_bytes(struct btrfs_block_group_cache *cache,
4190 u64 num_bytes, int reserve, int sinfo)
4194 struct btrfs_space_info *space_info = cache->space_info;
4195 spin_lock(&space_info->lock);
4196 spin_lock(&cache->lock);
4201 cache->reserved += num_bytes;
4202 space_info->bytes_reserved += num_bytes;
4206 space_info->bytes_readonly += num_bytes;
4207 cache->reserved -= num_bytes;
4208 space_info->bytes_reserved -= num_bytes;
4210 spin_unlock(&cache->lock);
4211 spin_unlock(&space_info->lock);
4213 spin_lock(&cache->lock);
4218 cache->reserved += num_bytes;
4220 cache->reserved -= num_bytes;
4222 spin_unlock(&cache->lock);
4227 int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
4228 struct btrfs_root *root)
4230 struct btrfs_fs_info *fs_info = root->fs_info;
4231 struct btrfs_caching_control *next;
4232 struct btrfs_caching_control *caching_ctl;
4233 struct btrfs_block_group_cache *cache;
4235 down_write(&fs_info->extent_commit_sem);
4237 list_for_each_entry_safe(caching_ctl, next,
4238 &fs_info->caching_block_groups, list) {
4239 cache = caching_ctl->block_group;
4240 if (block_group_cache_done(cache)) {
4241 cache->last_byte_to_unpin = (u64)-1;
4242 list_del_init(&caching_ctl->list);
4243 put_caching_control(caching_ctl);
4245 cache->last_byte_to_unpin = caching_ctl->progress;
4249 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4250 fs_info->pinned_extents = &fs_info->freed_extents[1];
4252 fs_info->pinned_extents = &fs_info->freed_extents[0];
4254 up_write(&fs_info->extent_commit_sem);
4256 update_global_block_rsv(fs_info);
4260 static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
4262 struct btrfs_fs_info *fs_info = root->fs_info;
4263 struct btrfs_block_group_cache *cache = NULL;
4266 while (start <= end) {
4268 start >= cache->key.objectid + cache->key.offset) {
4270 btrfs_put_block_group(cache);
4271 cache = btrfs_lookup_block_group(fs_info, start);
4275 len = cache->key.objectid + cache->key.offset - start;
4276 len = min(len, end + 1 - start);
4278 if (start < cache->last_byte_to_unpin) {
4279 len = min(len, cache->last_byte_to_unpin - start);
4280 btrfs_add_free_space(cache, start, len);
4285 spin_lock(&cache->space_info->lock);
4286 spin_lock(&cache->lock);
4287 cache->pinned -= len;
4288 cache->space_info->bytes_pinned -= len;
4290 cache->space_info->bytes_readonly += len;
4291 } else if (cache->reserved_pinned > 0) {
4292 len = min(len, cache->reserved_pinned);
4293 cache->reserved_pinned -= len;
4294 cache->space_info->bytes_reserved += len;
4296 spin_unlock(&cache->lock);
4297 spin_unlock(&cache->space_info->lock);
4301 btrfs_put_block_group(cache);
4305 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
4306 struct btrfs_root *root)
4308 struct btrfs_fs_info *fs_info = root->fs_info;
4309 struct extent_io_tree *unpin;
4310 struct btrfs_block_rsv *block_rsv;
4311 struct btrfs_block_rsv *next_rsv;
4317 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4318 unpin = &fs_info->freed_extents[1];
4320 unpin = &fs_info->freed_extents[0];
4323 ret = find_first_extent_bit(unpin, 0, &start, &end,
4328 ret = btrfs_discard_extent(root, start, end + 1 - start);
4330 clear_extent_dirty(unpin, start, end, GFP_NOFS);
4331 unpin_extent_range(root, start, end);
4335 mutex_lock(&fs_info->durable_block_rsv_mutex);
4336 list_for_each_entry_safe(block_rsv, next_rsv,
4337 &fs_info->durable_block_rsv_list, list) {
4339 idx = trans->transid & 0x1;
4340 if (block_rsv->freed[idx] > 0) {
4341 block_rsv_add_bytes(block_rsv,
4342 block_rsv->freed[idx], 0);
4343 block_rsv->freed[idx] = 0;
4345 if (atomic_read(&block_rsv->usage) == 0) {
4346 btrfs_block_rsv_release(root, block_rsv, (u64)-1);
4348 if (block_rsv->freed[0] == 0 &&
4349 block_rsv->freed[1] == 0) {
4350 list_del_init(&block_rsv->list);
4354 btrfs_block_rsv_release(root, block_rsv, 0);
4357 mutex_unlock(&fs_info->durable_block_rsv_mutex);
4362 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
4363 struct btrfs_root *root,
4364 u64 bytenr, u64 num_bytes, u64 parent,
4365 u64 root_objectid, u64 owner_objectid,
4366 u64 owner_offset, int refs_to_drop,
4367 struct btrfs_delayed_extent_op *extent_op)
4369 struct btrfs_key key;
4370 struct btrfs_path *path;
4371 struct btrfs_fs_info *info = root->fs_info;
4372 struct btrfs_root *extent_root = info->extent_root;
4373 struct extent_buffer *leaf;
4374 struct btrfs_extent_item *ei;
4375 struct btrfs_extent_inline_ref *iref;
4378 int extent_slot = 0;
4379 int found_extent = 0;
4384 path = btrfs_alloc_path();
4389 path->leave_spinning = 1;
4391 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
4392 BUG_ON(!is_data && refs_to_drop != 1);
4394 ret = lookup_extent_backref(trans, extent_root, path, &iref,
4395 bytenr, num_bytes, parent,
4396 root_objectid, owner_objectid,
4399 extent_slot = path->slots[0];
4400 while (extent_slot >= 0) {
4401 btrfs_item_key_to_cpu(path->nodes[0], &key,
4403 if (key.objectid != bytenr)
4405 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
4406 key.offset == num_bytes) {
4410 if (path->slots[0] - extent_slot > 5)
4414 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4415 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
4416 if (found_extent && item_size < sizeof(*ei))
4419 if (!found_extent) {
4421 ret = remove_extent_backref(trans, extent_root, path,
4425 btrfs_release_path(extent_root, path);
4426 path->leave_spinning = 1;
4428 key.objectid = bytenr;
4429 key.type = BTRFS_EXTENT_ITEM_KEY;
4430 key.offset = num_bytes;
4432 ret = btrfs_search_slot(trans, extent_root,
4435 printk(KERN_ERR "umm, got %d back from search"
4436 ", was looking for %llu\n", ret,
4437 (unsigned long long)bytenr);
4438 btrfs_print_leaf(extent_root, path->nodes[0]);
4441 extent_slot = path->slots[0];
4444 btrfs_print_leaf(extent_root, path->nodes[0]);
4446 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
4447 "parent %llu root %llu owner %llu offset %llu\n",
4448 (unsigned long long)bytenr,
4449 (unsigned long long)parent,
4450 (unsigned long long)root_objectid,
4451 (unsigned long long)owner_objectid,
4452 (unsigned long long)owner_offset);
4455 leaf = path->nodes[0];
4456 item_size = btrfs_item_size_nr(leaf, extent_slot);
4457 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4458 if (item_size < sizeof(*ei)) {
4459 BUG_ON(found_extent || extent_slot != path->slots[0]);
4460 ret = convert_extent_item_v0(trans, extent_root, path,
4464 btrfs_release_path(extent_root, path);
4465 path->leave_spinning = 1;
4467 key.objectid = bytenr;
4468 key.type = BTRFS_EXTENT_ITEM_KEY;
4469 key.offset = num_bytes;
4471 ret = btrfs_search_slot(trans, extent_root, &key, path,
4474 printk(KERN_ERR "umm, got %d back from search"
4475 ", was looking for %llu\n", ret,
4476 (unsigned long long)bytenr);
4477 btrfs_print_leaf(extent_root, path->nodes[0]);
4480 extent_slot = path->slots[0];
4481 leaf = path->nodes[0];
4482 item_size = btrfs_item_size_nr(leaf, extent_slot);
4485 BUG_ON(item_size < sizeof(*ei));
4486 ei = btrfs_item_ptr(leaf, extent_slot,
4487 struct btrfs_extent_item);
4488 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
4489 struct btrfs_tree_block_info *bi;
4490 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
4491 bi = (struct btrfs_tree_block_info *)(ei + 1);
4492 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
4495 refs = btrfs_extent_refs(leaf, ei);
4496 BUG_ON(refs < refs_to_drop);
4497 refs -= refs_to_drop;
4501 __run_delayed_extent_op(extent_op, leaf, ei);
4503 * In the case of inline back ref, reference count will
4504 * be updated by remove_extent_backref
4507 BUG_ON(!found_extent);
4509 btrfs_set_extent_refs(leaf, ei, refs);
4510 btrfs_mark_buffer_dirty(leaf);
4513 ret = remove_extent_backref(trans, extent_root, path,
4520 BUG_ON(is_data && refs_to_drop !=
4521 extent_data_ref_count(root, path, iref));
4523 BUG_ON(path->slots[0] != extent_slot);
4525 BUG_ON(path->slots[0] != extent_slot + 1);
4526 path->slots[0] = extent_slot;
4531 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
4534 btrfs_release_path(extent_root, path);
4537 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
4540 invalidate_mapping_pages(info->btree_inode->i_mapping,
4541 bytenr >> PAGE_CACHE_SHIFT,
4542 (bytenr + num_bytes - 1) >> PAGE_CACHE_SHIFT);
4545 ret = update_block_group(trans, root, bytenr, num_bytes, 0);
4548 btrfs_free_path(path);
4553 * when we free an block, it is possible (and likely) that we free the last
4554 * delayed ref for that extent as well. This searches the delayed ref tree for
4555 * a given extent, and if there are no other delayed refs to be processed, it
4556 * removes it from the tree.
4558 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
4559 struct btrfs_root *root, u64 bytenr)
4561 struct btrfs_delayed_ref_head *head;
4562 struct btrfs_delayed_ref_root *delayed_refs;
4563 struct btrfs_delayed_ref_node *ref;
4564 struct rb_node *node;
4567 delayed_refs = &trans->transaction->delayed_refs;
4568 spin_lock(&delayed_refs->lock);
4569 head = btrfs_find_delayed_ref_head(trans, bytenr);
4573 node = rb_prev(&head->node.rb_node);
4577 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
4579 /* there are still entries for this ref, we can't drop it */
4580 if (ref->bytenr == bytenr)
4583 if (head->extent_op) {
4584 if (!head->must_insert_reserved)
4586 kfree(head->extent_op);
4587 head->extent_op = NULL;
4591 * waiting for the lock here would deadlock. If someone else has it
4592 * locked they are already in the process of dropping it anyway
4594 if (!mutex_trylock(&head->mutex))
4598 * at this point we have a head with no other entries. Go
4599 * ahead and process it.
4601 head->node.in_tree = 0;
4602 rb_erase(&head->node.rb_node, &delayed_refs->root);
4604 delayed_refs->num_entries--;
4607 * we don't take a ref on the node because we're removing it from the
4608 * tree, so we just steal the ref the tree was holding.
4610 delayed_refs->num_heads--;
4611 if (list_empty(&head->cluster))
4612 delayed_refs->num_heads_ready--;
4614 list_del_init(&head->cluster);
4615 spin_unlock(&delayed_refs->lock);
4617 BUG_ON(head->extent_op);
4618 if (head->must_insert_reserved)
4621 mutex_unlock(&head->mutex);
4622 btrfs_put_delayed_ref(&head->node);
4625 spin_unlock(&delayed_refs->lock);
4629 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
4630 struct btrfs_root *root,
4631 struct extent_buffer *buf,
4632 u64 parent, int last_ref)
4634 struct btrfs_block_rsv *block_rsv;
4635 struct btrfs_block_group_cache *cache = NULL;
4638 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4639 ret = btrfs_add_delayed_tree_ref(trans, buf->start, buf->len,
4640 parent, root->root_key.objectid,
4641 btrfs_header_level(buf),
4642 BTRFS_DROP_DELAYED_REF, NULL);
4649 block_rsv = get_block_rsv(trans, root);
4650 cache = btrfs_lookup_block_group(root->fs_info, buf->start);
4651 if (block_rsv->space_info != cache->space_info)
4654 if (btrfs_header_generation(buf) == trans->transid) {
4655 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4656 ret = check_ref_cleanup(trans, root, buf->start);
4661 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
4662 pin_down_extent(root, cache, buf->start, buf->len, 1);
4666 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
4668 btrfs_add_free_space(cache, buf->start, buf->len);
4669 ret = update_reserved_bytes(cache, buf->len, 0, 0);
4670 if (ret == -EAGAIN) {
4671 /* block group became read-only */
4672 update_reserved_bytes(cache, buf->len, 0, 1);
4677 spin_lock(&block_rsv->lock);
4678 if (block_rsv->reserved < block_rsv->size) {
4679 block_rsv->reserved += buf->len;
4682 spin_unlock(&block_rsv->lock);
4685 spin_lock(&cache->space_info->lock);
4686 cache->space_info->bytes_reserved -= buf->len;
4687 spin_unlock(&cache->space_info->lock);
4692 if (block_rsv->durable && !cache->ro) {
4694 spin_lock(&cache->lock);
4696 cache->reserved_pinned += buf->len;
4699 spin_unlock(&cache->lock);
4702 spin_lock(&block_rsv->lock);
4703 block_rsv->freed[trans->transid & 0x1] += buf->len;
4704 spin_unlock(&block_rsv->lock);
4708 btrfs_put_block_group(cache);
4711 int btrfs_free_extent(struct btrfs_trans_handle *trans,
4712 struct btrfs_root *root,
4713 u64 bytenr, u64 num_bytes, u64 parent,
4714 u64 root_objectid, u64 owner, u64 offset)
4719 * tree log blocks never actually go into the extent allocation
4720 * tree, just update pinning info and exit early.
4722 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
4723 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
4724 /* unlocks the pinned mutex */
4725 btrfs_pin_extent(root, bytenr, num_bytes, 1);
4727 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
4728 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
4729 parent, root_objectid, (int)owner,
4730 BTRFS_DROP_DELAYED_REF, NULL);
4733 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
4734 parent, root_objectid, owner,
4735 offset, BTRFS_DROP_DELAYED_REF, NULL);
4741 static u64 stripe_align(struct btrfs_root *root, u64 val)
4743 u64 mask = ((u64)root->stripesize - 1);
4744 u64 ret = (val + mask) & ~mask;
4749 * when we wait for progress in the block group caching, its because
4750 * our allocation attempt failed at least once. So, we must sleep
4751 * and let some progress happen before we try again.
4753 * This function will sleep at least once waiting for new free space to
4754 * show up, and then it will check the block group free space numbers
4755 * for our min num_bytes. Another option is to have it go ahead
4756 * and look in the rbtree for a free extent of a given size, but this
4760 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
4763 struct btrfs_caching_control *caching_ctl;
4766 caching_ctl = get_caching_control(cache);
4770 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
4771 (cache->free_space >= num_bytes));
4773 put_caching_control(caching_ctl);
4778 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
4780 struct btrfs_caching_control *caching_ctl;
4783 caching_ctl = get_caching_control(cache);
4787 wait_event(caching_ctl->wait, block_group_cache_done(cache));
4789 put_caching_control(caching_ctl);
4793 static int get_block_group_index(struct btrfs_block_group_cache *cache)
4796 if (cache->flags & BTRFS_BLOCK_GROUP_RAID10)
4798 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID1)
4800 else if (cache->flags & BTRFS_BLOCK_GROUP_DUP)
4802 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID0)
4809 enum btrfs_loop_type {
4810 LOOP_FIND_IDEAL = 0,
4811 LOOP_CACHING_NOWAIT = 1,
4812 LOOP_CACHING_WAIT = 2,
4813 LOOP_ALLOC_CHUNK = 3,
4814 LOOP_NO_EMPTY_SIZE = 4,
4818 * walks the btree of allocated extents and find a hole of a given size.
4819 * The key ins is changed to record the hole:
4820 * ins->objectid == block start
4821 * ins->flags = BTRFS_EXTENT_ITEM_KEY
4822 * ins->offset == number of blocks
4823 * Any available blocks before search_start are skipped.
4825 static noinline int find_free_extent(struct btrfs_trans_handle *trans,
4826 struct btrfs_root *orig_root,
4827 u64 num_bytes, u64 empty_size,
4828 u64 search_start, u64 search_end,
4829 u64 hint_byte, struct btrfs_key *ins,
4833 struct btrfs_root *root = orig_root->fs_info->extent_root;
4834 struct btrfs_free_cluster *last_ptr = NULL;
4835 struct btrfs_block_group_cache *block_group = NULL;
4836 int empty_cluster = 2 * 1024 * 1024;
4837 int allowed_chunk_alloc = 0;
4838 int done_chunk_alloc = 0;
4839 struct btrfs_space_info *space_info;
4840 int last_ptr_loop = 0;
4843 bool found_uncached_bg = false;
4844 bool failed_cluster_refill = false;
4845 bool failed_alloc = false;
4846 bool use_cluster = true;
4847 u64 ideal_cache_percent = 0;
4848 u64 ideal_cache_offset = 0;
4850 WARN_ON(num_bytes < root->sectorsize);
4851 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
4855 space_info = __find_space_info(root->fs_info, data);
4857 printk(KERN_ERR "No space info for %d\n", data);
4862 * If the space info is for both data and metadata it means we have a
4863 * small filesystem and we can't use the clustering stuff.
4865 if (btrfs_mixed_space_info(space_info))
4866 use_cluster = false;
4868 if (orig_root->ref_cows || empty_size)
4869 allowed_chunk_alloc = 1;
4871 if (data & BTRFS_BLOCK_GROUP_METADATA && use_cluster) {
4872 last_ptr = &root->fs_info->meta_alloc_cluster;
4873 if (!btrfs_test_opt(root, SSD))
4874 empty_cluster = 64 * 1024;
4877 if ((data & BTRFS_BLOCK_GROUP_DATA) && use_cluster &&
4878 btrfs_test_opt(root, SSD)) {
4879 last_ptr = &root->fs_info->data_alloc_cluster;
4883 spin_lock(&last_ptr->lock);
4884 if (last_ptr->block_group)
4885 hint_byte = last_ptr->window_start;
4886 spin_unlock(&last_ptr->lock);
4889 search_start = max(search_start, first_logical_byte(root, 0));
4890 search_start = max(search_start, hint_byte);
4895 if (search_start == hint_byte) {
4897 block_group = btrfs_lookup_block_group(root->fs_info,
4900 * we don't want to use the block group if it doesn't match our
4901 * allocation bits, or if its not cached.
4903 * However if we are re-searching with an ideal block group
4904 * picked out then we don't care that the block group is cached.
4906 if (block_group && block_group_bits(block_group, data) &&
4907 (block_group->cached != BTRFS_CACHE_NO ||
4908 search_start == ideal_cache_offset)) {
4909 down_read(&space_info->groups_sem);
4910 if (list_empty(&block_group->list) ||
4913 * someone is removing this block group,
4914 * we can't jump into the have_block_group
4915 * target because our list pointers are not
4918 btrfs_put_block_group(block_group);
4919 up_read(&space_info->groups_sem);
4921 index = get_block_group_index(block_group);
4922 goto have_block_group;
4924 } else if (block_group) {
4925 btrfs_put_block_group(block_group);
4929 down_read(&space_info->groups_sem);
4930 list_for_each_entry(block_group, &space_info->block_groups[index],
4935 btrfs_get_block_group(block_group);
4936 search_start = block_group->key.objectid;
4939 if (unlikely(block_group->cached == BTRFS_CACHE_NO)) {
4942 ret = cache_block_group(block_group, trans, 1);
4943 if (block_group->cached == BTRFS_CACHE_FINISHED)
4944 goto have_block_group;
4946 free_percent = btrfs_block_group_used(&block_group->item);
4947 free_percent *= 100;
4948 free_percent = div64_u64(free_percent,
4949 block_group->key.offset);
4950 free_percent = 100 - free_percent;
4951 if (free_percent > ideal_cache_percent &&
4952 likely(!block_group->ro)) {
4953 ideal_cache_offset = block_group->key.objectid;
4954 ideal_cache_percent = free_percent;
4958 * We only want to start kthread caching if we are at
4959 * the point where we will wait for caching to make
4960 * progress, or if our ideal search is over and we've
4961 * found somebody to start caching.
4963 if (loop > LOOP_CACHING_NOWAIT ||
4964 (loop > LOOP_FIND_IDEAL &&
4965 atomic_read(&space_info->caching_threads) < 2)) {
4966 ret = cache_block_group(block_group, trans, 0);
4969 found_uncached_bg = true;
4972 * If loop is set for cached only, try the next block
4975 if (loop == LOOP_FIND_IDEAL)
4979 cached = block_group_cache_done(block_group);
4980 if (unlikely(!cached))
4981 found_uncached_bg = true;
4983 if (unlikely(block_group->ro))
4987 * Ok we want to try and use the cluster allocator, so lets look
4988 * there, unless we are on LOOP_NO_EMPTY_SIZE, since we will
4989 * have tried the cluster allocator plenty of times at this
4990 * point and not have found anything, so we are likely way too
4991 * fragmented for the clustering stuff to find anything, so lets
4992 * just skip it and let the allocator find whatever block it can
4995 if (last_ptr && loop < LOOP_NO_EMPTY_SIZE) {
4997 * the refill lock keeps out other
4998 * people trying to start a new cluster
5000 spin_lock(&last_ptr->refill_lock);
5001 if (last_ptr->block_group &&
5002 (last_ptr->block_group->ro ||
5003 !block_group_bits(last_ptr->block_group, data))) {
5005 goto refill_cluster;
5008 offset = btrfs_alloc_from_cluster(block_group, last_ptr,
5009 num_bytes, search_start);
5011 /* we have a block, we're done */
5012 spin_unlock(&last_ptr->refill_lock);
5016 spin_lock(&last_ptr->lock);
5018 * whoops, this cluster doesn't actually point to
5019 * this block group. Get a ref on the block
5020 * group is does point to and try again
5022 if (!last_ptr_loop && last_ptr->block_group &&
5023 last_ptr->block_group != block_group) {
5025 btrfs_put_block_group(block_group);
5026 block_group = last_ptr->block_group;
5027 btrfs_get_block_group(block_group);
5028 spin_unlock(&last_ptr->lock);
5029 spin_unlock(&last_ptr->refill_lock);
5032 search_start = block_group->key.objectid;
5034 * we know this block group is properly
5035 * in the list because
5036 * btrfs_remove_block_group, drops the
5037 * cluster before it removes the block
5038 * group from the list
5040 goto have_block_group;
5042 spin_unlock(&last_ptr->lock);
5045 * this cluster didn't work out, free it and
5048 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5052 /* allocate a cluster in this block group */
5053 ret = btrfs_find_space_cluster(trans, root,
5054 block_group, last_ptr,
5056 empty_cluster + empty_size);
5059 * now pull our allocation out of this
5062 offset = btrfs_alloc_from_cluster(block_group,
5063 last_ptr, num_bytes,
5066 /* we found one, proceed */
5067 spin_unlock(&last_ptr->refill_lock);
5070 } else if (!cached && loop > LOOP_CACHING_NOWAIT
5071 && !failed_cluster_refill) {
5072 spin_unlock(&last_ptr->refill_lock);
5074 failed_cluster_refill = true;
5075 wait_block_group_cache_progress(block_group,
5076 num_bytes + empty_cluster + empty_size);
5077 goto have_block_group;
5081 * at this point we either didn't find a cluster
5082 * or we weren't able to allocate a block from our
5083 * cluster. Free the cluster we've been trying
5084 * to use, and go to the next block group
5086 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5087 spin_unlock(&last_ptr->refill_lock);
5091 offset = btrfs_find_space_for_alloc(block_group, search_start,
5092 num_bytes, empty_size);
5094 * If we didn't find a chunk, and we haven't failed on this
5095 * block group before, and this block group is in the middle of
5096 * caching and we are ok with waiting, then go ahead and wait
5097 * for progress to be made, and set failed_alloc to true.
5099 * If failed_alloc is true then we've already waited on this
5100 * block group once and should move on to the next block group.
5102 if (!offset && !failed_alloc && !cached &&
5103 loop > LOOP_CACHING_NOWAIT) {
5104 wait_block_group_cache_progress(block_group,
5105 num_bytes + empty_size);
5106 failed_alloc = true;
5107 goto have_block_group;
5108 } else if (!offset) {
5112 search_start = stripe_align(root, offset);
5113 /* move on to the next group */
5114 if (search_start + num_bytes >= search_end) {
5115 btrfs_add_free_space(block_group, offset, num_bytes);
5119 /* move on to the next group */
5120 if (search_start + num_bytes >
5121 block_group->key.objectid + block_group->key.offset) {
5122 btrfs_add_free_space(block_group, offset, num_bytes);
5126 ins->objectid = search_start;
5127 ins->offset = num_bytes;
5129 if (offset < search_start)
5130 btrfs_add_free_space(block_group, offset,
5131 search_start - offset);
5132 BUG_ON(offset > search_start);
5134 ret = update_reserved_bytes(block_group, num_bytes, 1,
5135 (data & BTRFS_BLOCK_GROUP_DATA));
5136 if (ret == -EAGAIN) {
5137 btrfs_add_free_space(block_group, offset, num_bytes);
5141 /* we are all good, lets return */
5142 ins->objectid = search_start;
5143 ins->offset = num_bytes;
5145 if (offset < search_start)
5146 btrfs_add_free_space(block_group, offset,
5147 search_start - offset);
5148 BUG_ON(offset > search_start);
5151 failed_cluster_refill = false;
5152 failed_alloc = false;
5153 BUG_ON(index != get_block_group_index(block_group));
5154 btrfs_put_block_group(block_group);
5156 up_read(&space_info->groups_sem);
5158 if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES)
5161 /* LOOP_FIND_IDEAL, only search caching/cached bg's, and don't wait for
5162 * for them to make caching progress. Also
5163 * determine the best possible bg to cache
5164 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
5165 * caching kthreads as we move along
5166 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
5167 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
5168 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
5171 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE &&
5172 (found_uncached_bg || empty_size || empty_cluster ||
5173 allowed_chunk_alloc)) {
5175 if (loop == LOOP_FIND_IDEAL && found_uncached_bg) {
5176 found_uncached_bg = false;
5178 if (!ideal_cache_percent &&
5179 atomic_read(&space_info->caching_threads))
5183 * 1 of the following 2 things have happened so far
5185 * 1) We found an ideal block group for caching that
5186 * is mostly full and will cache quickly, so we might
5187 * as well wait for it.
5189 * 2) We searched for cached only and we didn't find
5190 * anything, and we didn't start any caching kthreads
5191 * either, so chances are we will loop through and
5192 * start a couple caching kthreads, and then come back
5193 * around and just wait for them. This will be slower
5194 * because we will have 2 caching kthreads reading at
5195 * the same time when we could have just started one
5196 * and waited for it to get far enough to give us an
5197 * allocation, so go ahead and go to the wait caching
5200 loop = LOOP_CACHING_WAIT;
5201 search_start = ideal_cache_offset;
5202 ideal_cache_percent = 0;
5204 } else if (loop == LOOP_FIND_IDEAL) {
5206 * Didn't find a uncached bg, wait on anything we find
5209 loop = LOOP_CACHING_WAIT;
5213 if (loop < LOOP_CACHING_WAIT) {
5218 if (loop == LOOP_ALLOC_CHUNK) {
5223 if (allowed_chunk_alloc) {
5224 ret = do_chunk_alloc(trans, root, num_bytes +
5225 2 * 1024 * 1024, data, 1);
5226 allowed_chunk_alloc = 0;
5227 done_chunk_alloc = 1;
5228 } else if (!done_chunk_alloc) {
5229 space_info->force_alloc = 1;
5232 if (loop < LOOP_NO_EMPTY_SIZE) {
5237 } else if (!ins->objectid) {
5241 /* we found what we needed */
5242 if (ins->objectid) {
5243 if (!(data & BTRFS_BLOCK_GROUP_DATA))
5244 trans->block_group = block_group->key.objectid;
5246 btrfs_put_block_group(block_group);
5253 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
5254 int dump_block_groups)
5256 struct btrfs_block_group_cache *cache;
5259 spin_lock(&info->lock);
5260 printk(KERN_INFO "space_info has %llu free, is %sfull\n",
5261 (unsigned long long)(info->total_bytes - info->bytes_used -
5262 info->bytes_pinned - info->bytes_reserved -
5263 info->bytes_readonly),
5264 (info->full) ? "" : "not ");
5265 printk(KERN_INFO "space_info total=%llu, used=%llu, pinned=%llu, "
5266 "reserved=%llu, may_use=%llu, readonly=%llu\n",
5267 (unsigned long long)info->total_bytes,
5268 (unsigned long long)info->bytes_used,
5269 (unsigned long long)info->bytes_pinned,
5270 (unsigned long long)info->bytes_reserved,
5271 (unsigned long long)info->bytes_may_use,
5272 (unsigned long long)info->bytes_readonly);
5273 spin_unlock(&info->lock);
5275 if (!dump_block_groups)
5278 down_read(&info->groups_sem);
5280 list_for_each_entry(cache, &info->block_groups[index], list) {
5281 spin_lock(&cache->lock);
5282 printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
5283 "%llu pinned %llu reserved\n",
5284 (unsigned long long)cache->key.objectid,
5285 (unsigned long long)cache->key.offset,
5286 (unsigned long long)btrfs_block_group_used(&cache->item),
5287 (unsigned long long)cache->pinned,
5288 (unsigned long long)cache->reserved);
5289 btrfs_dump_free_space(cache, bytes);
5290 spin_unlock(&cache->lock);
5292 if (++index < BTRFS_NR_RAID_TYPES)
5294 up_read(&info->groups_sem);
5297 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
5298 struct btrfs_root *root,
5299 u64 num_bytes, u64 min_alloc_size,
5300 u64 empty_size, u64 hint_byte,
5301 u64 search_end, struct btrfs_key *ins,
5305 u64 search_start = 0;
5307 data = btrfs_get_alloc_profile(root, data);
5310 * the only place that sets empty_size is btrfs_realloc_node, which
5311 * is not called recursively on allocations
5313 if (empty_size || root->ref_cows)
5314 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
5315 num_bytes + 2 * 1024 * 1024, data, 0);
5317 WARN_ON(num_bytes < root->sectorsize);
5318 ret = find_free_extent(trans, root, num_bytes, empty_size,
5319 search_start, search_end, hint_byte,
5322 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
5323 num_bytes = num_bytes >> 1;
5324 num_bytes = num_bytes & ~(root->sectorsize - 1);
5325 num_bytes = max(num_bytes, min_alloc_size);
5326 do_chunk_alloc(trans, root->fs_info->extent_root,
5327 num_bytes, data, 1);
5330 if (ret == -ENOSPC) {
5331 struct btrfs_space_info *sinfo;
5333 sinfo = __find_space_info(root->fs_info, data);
5334 printk(KERN_ERR "btrfs allocation failed flags %llu, "
5335 "wanted %llu\n", (unsigned long long)data,
5336 (unsigned long long)num_bytes);
5337 dump_space_info(sinfo, num_bytes, 1);
5343 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
5345 struct btrfs_block_group_cache *cache;
5348 cache = btrfs_lookup_block_group(root->fs_info, start);
5350 printk(KERN_ERR "Unable to find block group for %llu\n",
5351 (unsigned long long)start);
5355 ret = btrfs_discard_extent(root, start, len);
5357 btrfs_add_free_space(cache, start, len);
5358 update_reserved_bytes(cache, len, 0, 1);
5359 btrfs_put_block_group(cache);
5364 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5365 struct btrfs_root *root,
5366 u64 parent, u64 root_objectid,
5367 u64 flags, u64 owner, u64 offset,
5368 struct btrfs_key *ins, int ref_mod)
5371 struct btrfs_fs_info *fs_info = root->fs_info;
5372 struct btrfs_extent_item *extent_item;
5373 struct btrfs_extent_inline_ref *iref;
5374 struct btrfs_path *path;
5375 struct extent_buffer *leaf;
5380 type = BTRFS_SHARED_DATA_REF_KEY;
5382 type = BTRFS_EXTENT_DATA_REF_KEY;
5384 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
5386 path = btrfs_alloc_path();
5389 path->leave_spinning = 1;
5390 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5394 leaf = path->nodes[0];
5395 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5396 struct btrfs_extent_item);
5397 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
5398 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5399 btrfs_set_extent_flags(leaf, extent_item,
5400 flags | BTRFS_EXTENT_FLAG_DATA);
5402 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
5403 btrfs_set_extent_inline_ref_type(leaf, iref, type);
5405 struct btrfs_shared_data_ref *ref;
5406 ref = (struct btrfs_shared_data_ref *)(iref + 1);
5407 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5408 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
5410 struct btrfs_extent_data_ref *ref;
5411 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
5412 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
5413 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
5414 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
5415 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
5418 btrfs_mark_buffer_dirty(path->nodes[0]);
5419 btrfs_free_path(path);
5421 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5423 printk(KERN_ERR "btrfs update block group failed for %llu "
5424 "%llu\n", (unsigned long long)ins->objectid,
5425 (unsigned long long)ins->offset);
5431 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
5432 struct btrfs_root *root,
5433 u64 parent, u64 root_objectid,
5434 u64 flags, struct btrfs_disk_key *key,
5435 int level, struct btrfs_key *ins)
5438 struct btrfs_fs_info *fs_info = root->fs_info;
5439 struct btrfs_extent_item *extent_item;
5440 struct btrfs_tree_block_info *block_info;
5441 struct btrfs_extent_inline_ref *iref;
5442 struct btrfs_path *path;
5443 struct extent_buffer *leaf;
5444 u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref);
5446 path = btrfs_alloc_path();
5449 path->leave_spinning = 1;
5450 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5454 leaf = path->nodes[0];
5455 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5456 struct btrfs_extent_item);
5457 btrfs_set_extent_refs(leaf, extent_item, 1);
5458 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5459 btrfs_set_extent_flags(leaf, extent_item,
5460 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
5461 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
5463 btrfs_set_tree_block_key(leaf, block_info, key);
5464 btrfs_set_tree_block_level(leaf, block_info, level);
5466 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
5468 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
5469 btrfs_set_extent_inline_ref_type(leaf, iref,
5470 BTRFS_SHARED_BLOCK_REF_KEY);
5471 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5473 btrfs_set_extent_inline_ref_type(leaf, iref,
5474 BTRFS_TREE_BLOCK_REF_KEY);
5475 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
5478 btrfs_mark_buffer_dirty(leaf);
5479 btrfs_free_path(path);
5481 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5483 printk(KERN_ERR "btrfs update block group failed for %llu "
5484 "%llu\n", (unsigned long long)ins->objectid,
5485 (unsigned long long)ins->offset);
5491 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5492 struct btrfs_root *root,
5493 u64 root_objectid, u64 owner,
5494 u64 offset, struct btrfs_key *ins)
5498 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
5500 ret = btrfs_add_delayed_data_ref(trans, ins->objectid, ins->offset,
5501 0, root_objectid, owner, offset,
5502 BTRFS_ADD_DELAYED_EXTENT, NULL);
5507 * this is used by the tree logging recovery code. It records that
5508 * an extent has been allocated and makes sure to clear the free
5509 * space cache bits as well
5511 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
5512 struct btrfs_root *root,
5513 u64 root_objectid, u64 owner, u64 offset,
5514 struct btrfs_key *ins)
5517 struct btrfs_block_group_cache *block_group;
5518 struct btrfs_caching_control *caching_ctl;
5519 u64 start = ins->objectid;
5520 u64 num_bytes = ins->offset;
5522 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
5523 cache_block_group(block_group, trans, 0);
5524 caching_ctl = get_caching_control(block_group);
5527 BUG_ON(!block_group_cache_done(block_group));
5528 ret = btrfs_remove_free_space(block_group, start, num_bytes);
5531 mutex_lock(&caching_ctl->mutex);
5533 if (start >= caching_ctl->progress) {
5534 ret = add_excluded_extent(root, start, num_bytes);
5536 } else if (start + num_bytes <= caching_ctl->progress) {
5537 ret = btrfs_remove_free_space(block_group,
5541 num_bytes = caching_ctl->progress - start;
5542 ret = btrfs_remove_free_space(block_group,
5546 start = caching_ctl->progress;
5547 num_bytes = ins->objectid + ins->offset -
5548 caching_ctl->progress;
5549 ret = add_excluded_extent(root, start, num_bytes);
5553 mutex_unlock(&caching_ctl->mutex);
5554 put_caching_control(caching_ctl);
5557 ret = update_reserved_bytes(block_group, ins->offset, 1, 1);
5559 btrfs_put_block_group(block_group);
5560 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
5561 0, owner, offset, ins, 1);
5565 struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
5566 struct btrfs_root *root,
5567 u64 bytenr, u32 blocksize,
5570 struct extent_buffer *buf;
5572 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
5574 return ERR_PTR(-ENOMEM);
5575 btrfs_set_header_generation(buf, trans->transid);
5576 btrfs_set_buffer_lockdep_class(buf, level);
5577 btrfs_tree_lock(buf);
5578 clean_tree_block(trans, root, buf);
5580 btrfs_set_lock_blocking(buf);
5581 btrfs_set_buffer_uptodate(buf);
5583 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
5585 * we allow two log transactions at a time, use different
5586 * EXENT bit to differentiate dirty pages.
5588 if (root->log_transid % 2 == 0)
5589 set_extent_dirty(&root->dirty_log_pages, buf->start,
5590 buf->start + buf->len - 1, GFP_NOFS);
5592 set_extent_new(&root->dirty_log_pages, buf->start,
5593 buf->start + buf->len - 1, GFP_NOFS);
5595 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
5596 buf->start + buf->len - 1, GFP_NOFS);
5598 trans->blocks_used++;
5599 /* this returns a buffer locked for blocking */
5603 static struct btrfs_block_rsv *
5604 use_block_rsv(struct btrfs_trans_handle *trans,
5605 struct btrfs_root *root, u32 blocksize)
5607 struct btrfs_block_rsv *block_rsv;
5610 block_rsv = get_block_rsv(trans, root);
5612 if (block_rsv->size == 0) {
5613 ret = reserve_metadata_bytes(trans, root, block_rsv,
5616 return ERR_PTR(ret);
5620 ret = block_rsv_use_bytes(block_rsv, blocksize);
5624 return ERR_PTR(-ENOSPC);
5627 static void unuse_block_rsv(struct btrfs_block_rsv *block_rsv, u32 blocksize)
5629 block_rsv_add_bytes(block_rsv, blocksize, 0);
5630 block_rsv_release_bytes(block_rsv, NULL, 0);
5634 * finds a free extent and does all the dirty work required for allocation
5635 * returns the key for the extent through ins, and a tree buffer for
5636 * the first block of the extent through buf.
5638 * returns the tree buffer or NULL.
5640 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
5641 struct btrfs_root *root, u32 blocksize,
5642 u64 parent, u64 root_objectid,
5643 struct btrfs_disk_key *key, int level,
5644 u64 hint, u64 empty_size)
5646 struct btrfs_key ins;
5647 struct btrfs_block_rsv *block_rsv;
5648 struct extent_buffer *buf;
5653 block_rsv = use_block_rsv(trans, root, blocksize);
5654 if (IS_ERR(block_rsv))
5655 return ERR_CAST(block_rsv);
5657 ret = btrfs_reserve_extent(trans, root, blocksize, blocksize,
5658 empty_size, hint, (u64)-1, &ins, 0);
5660 unuse_block_rsv(block_rsv, blocksize);
5661 return ERR_PTR(ret);
5664 buf = btrfs_init_new_buffer(trans, root, ins.objectid,
5666 BUG_ON(IS_ERR(buf));
5668 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
5670 parent = ins.objectid;
5671 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
5675 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
5676 struct btrfs_delayed_extent_op *extent_op;
5677 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
5680 memcpy(&extent_op->key, key, sizeof(extent_op->key));
5682 memset(&extent_op->key, 0, sizeof(extent_op->key));
5683 extent_op->flags_to_set = flags;
5684 extent_op->update_key = 1;
5685 extent_op->update_flags = 1;
5686 extent_op->is_data = 0;
5688 ret = btrfs_add_delayed_tree_ref(trans, ins.objectid,
5689 ins.offset, parent, root_objectid,
5690 level, BTRFS_ADD_DELAYED_EXTENT,
5697 struct walk_control {
5698 u64 refs[BTRFS_MAX_LEVEL];
5699 u64 flags[BTRFS_MAX_LEVEL];
5700 struct btrfs_key update_progress;
5710 #define DROP_REFERENCE 1
5711 #define UPDATE_BACKREF 2
5713 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
5714 struct btrfs_root *root,
5715 struct walk_control *wc,
5716 struct btrfs_path *path)
5724 struct btrfs_key key;
5725 struct extent_buffer *eb;
5730 if (path->slots[wc->level] < wc->reada_slot) {
5731 wc->reada_count = wc->reada_count * 2 / 3;
5732 wc->reada_count = max(wc->reada_count, 2);
5734 wc->reada_count = wc->reada_count * 3 / 2;
5735 wc->reada_count = min_t(int, wc->reada_count,
5736 BTRFS_NODEPTRS_PER_BLOCK(root));
5739 eb = path->nodes[wc->level];
5740 nritems = btrfs_header_nritems(eb);
5741 blocksize = btrfs_level_size(root, wc->level - 1);
5743 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
5744 if (nread >= wc->reada_count)
5748 bytenr = btrfs_node_blockptr(eb, slot);
5749 generation = btrfs_node_ptr_generation(eb, slot);
5751 if (slot == path->slots[wc->level])
5754 if (wc->stage == UPDATE_BACKREF &&
5755 generation <= root->root_key.offset)
5758 /* We don't lock the tree block, it's OK to be racy here */
5759 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5764 if (wc->stage == DROP_REFERENCE) {
5768 if (wc->level == 1 &&
5769 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5771 if (!wc->update_ref ||
5772 generation <= root->root_key.offset)
5774 btrfs_node_key_to_cpu(eb, &key, slot);
5775 ret = btrfs_comp_cpu_keys(&key,
5776 &wc->update_progress);
5780 if (wc->level == 1 &&
5781 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5785 ret = readahead_tree_block(root, bytenr, blocksize,
5791 wc->reada_slot = slot;
5795 * hepler to process tree block while walking down the tree.
5797 * when wc->stage == UPDATE_BACKREF, this function updates
5798 * back refs for pointers in the block.
5800 * NOTE: return value 1 means we should stop walking down.
5802 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
5803 struct btrfs_root *root,
5804 struct btrfs_path *path,
5805 struct walk_control *wc, int lookup_info)
5807 int level = wc->level;
5808 struct extent_buffer *eb = path->nodes[level];
5809 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5812 if (wc->stage == UPDATE_BACKREF &&
5813 btrfs_header_owner(eb) != root->root_key.objectid)
5817 * when reference count of tree block is 1, it won't increase
5818 * again. once full backref flag is set, we never clear it.
5821 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
5822 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
5823 BUG_ON(!path->locks[level]);
5824 ret = btrfs_lookup_extent_info(trans, root,
5829 BUG_ON(wc->refs[level] == 0);
5832 if (wc->stage == DROP_REFERENCE) {
5833 if (wc->refs[level] > 1)
5836 if (path->locks[level] && !wc->keep_locks) {
5837 btrfs_tree_unlock(eb);
5838 path->locks[level] = 0;
5843 /* wc->stage == UPDATE_BACKREF */
5844 if (!(wc->flags[level] & flag)) {
5845 BUG_ON(!path->locks[level]);
5846 ret = btrfs_inc_ref(trans, root, eb, 1);
5848 ret = btrfs_dec_ref(trans, root, eb, 0);
5850 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
5853 wc->flags[level] |= flag;
5857 * the block is shared by multiple trees, so it's not good to
5858 * keep the tree lock
5860 if (path->locks[level] && level > 0) {
5861 btrfs_tree_unlock(eb);
5862 path->locks[level] = 0;
5868 * hepler to process tree block pointer.
5870 * when wc->stage == DROP_REFERENCE, this function checks
5871 * reference count of the block pointed to. if the block
5872 * is shared and we need update back refs for the subtree
5873 * rooted at the block, this function changes wc->stage to
5874 * UPDATE_BACKREF. if the block is shared and there is no
5875 * need to update back, this function drops the reference
5878 * NOTE: return value 1 means we should stop walking down.
5880 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
5881 struct btrfs_root *root,
5882 struct btrfs_path *path,
5883 struct walk_control *wc, int *lookup_info)
5889 struct btrfs_key key;
5890 struct extent_buffer *next;
5891 int level = wc->level;
5895 generation = btrfs_node_ptr_generation(path->nodes[level],
5896 path->slots[level]);
5898 * if the lower level block was created before the snapshot
5899 * was created, we know there is no need to update back refs
5902 if (wc->stage == UPDATE_BACKREF &&
5903 generation <= root->root_key.offset) {
5908 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
5909 blocksize = btrfs_level_size(root, level - 1);
5911 next = btrfs_find_tree_block(root, bytenr, blocksize);
5913 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
5918 btrfs_tree_lock(next);
5919 btrfs_set_lock_blocking(next);
5921 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5922 &wc->refs[level - 1],
5923 &wc->flags[level - 1]);
5925 BUG_ON(wc->refs[level - 1] == 0);
5928 if (wc->stage == DROP_REFERENCE) {
5929 if (wc->refs[level - 1] > 1) {
5931 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5934 if (!wc->update_ref ||
5935 generation <= root->root_key.offset)
5938 btrfs_node_key_to_cpu(path->nodes[level], &key,
5939 path->slots[level]);
5940 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
5944 wc->stage = UPDATE_BACKREF;
5945 wc->shared_level = level - 1;
5949 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5953 if (!btrfs_buffer_uptodate(next, generation)) {
5954 btrfs_tree_unlock(next);
5955 free_extent_buffer(next);
5961 if (reada && level == 1)
5962 reada_walk_down(trans, root, wc, path);
5963 next = read_tree_block(root, bytenr, blocksize, generation);
5964 btrfs_tree_lock(next);
5965 btrfs_set_lock_blocking(next);
5969 BUG_ON(level != btrfs_header_level(next));
5970 path->nodes[level] = next;
5971 path->slots[level] = 0;
5972 path->locks[level] = 1;
5978 wc->refs[level - 1] = 0;
5979 wc->flags[level - 1] = 0;
5980 if (wc->stage == DROP_REFERENCE) {
5981 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
5982 parent = path->nodes[level]->start;
5984 BUG_ON(root->root_key.objectid !=
5985 btrfs_header_owner(path->nodes[level]));
5989 ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
5990 root->root_key.objectid, level - 1, 0);
5993 btrfs_tree_unlock(next);
5994 free_extent_buffer(next);
6000 * hepler to process tree block while walking up the tree.
6002 * when wc->stage == DROP_REFERENCE, this function drops
6003 * reference count on the block.
6005 * when wc->stage == UPDATE_BACKREF, this function changes
6006 * wc->stage back to DROP_REFERENCE if we changed wc->stage
6007 * to UPDATE_BACKREF previously while processing the block.
6009 * NOTE: return value 1 means we should stop walking up.
6011 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
6012 struct btrfs_root *root,
6013 struct btrfs_path *path,
6014 struct walk_control *wc)
6017 int level = wc->level;
6018 struct extent_buffer *eb = path->nodes[level];
6021 if (wc->stage == UPDATE_BACKREF) {
6022 BUG_ON(wc->shared_level < level);
6023 if (level < wc->shared_level)
6026 ret = find_next_key(path, level + 1, &wc->update_progress);
6030 wc->stage = DROP_REFERENCE;
6031 wc->shared_level = -1;
6032 path->slots[level] = 0;
6035 * check reference count again if the block isn't locked.
6036 * we should start walking down the tree again if reference
6039 if (!path->locks[level]) {
6041 btrfs_tree_lock(eb);
6042 btrfs_set_lock_blocking(eb);
6043 path->locks[level] = 1;
6045 ret = btrfs_lookup_extent_info(trans, root,
6050 BUG_ON(wc->refs[level] == 0);
6051 if (wc->refs[level] == 1) {
6052 btrfs_tree_unlock(eb);
6053 path->locks[level] = 0;
6059 /* wc->stage == DROP_REFERENCE */
6060 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
6062 if (wc->refs[level] == 1) {
6064 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6065 ret = btrfs_dec_ref(trans, root, eb, 1);
6067 ret = btrfs_dec_ref(trans, root, eb, 0);
6070 /* make block locked assertion in clean_tree_block happy */
6071 if (!path->locks[level] &&
6072 btrfs_header_generation(eb) == trans->transid) {
6073 btrfs_tree_lock(eb);
6074 btrfs_set_lock_blocking(eb);
6075 path->locks[level] = 1;
6077 clean_tree_block(trans, root, eb);
6080 if (eb == root->node) {
6081 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6084 BUG_ON(root->root_key.objectid !=
6085 btrfs_header_owner(eb));
6087 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6088 parent = path->nodes[level + 1]->start;
6090 BUG_ON(root->root_key.objectid !=
6091 btrfs_header_owner(path->nodes[level + 1]));
6094 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
6096 wc->refs[level] = 0;
6097 wc->flags[level] = 0;
6101 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
6102 struct btrfs_root *root,
6103 struct btrfs_path *path,
6104 struct walk_control *wc)
6106 int level = wc->level;
6107 int lookup_info = 1;
6110 while (level >= 0) {
6111 ret = walk_down_proc(trans, root, path, wc, lookup_info);
6118 if (path->slots[level] >=
6119 btrfs_header_nritems(path->nodes[level]))
6122 ret = do_walk_down(trans, root, path, wc, &lookup_info);
6124 path->slots[level]++;
6133 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
6134 struct btrfs_root *root,
6135 struct btrfs_path *path,
6136 struct walk_control *wc, int max_level)
6138 int level = wc->level;
6141 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
6142 while (level < max_level && path->nodes[level]) {
6144 if (path->slots[level] + 1 <
6145 btrfs_header_nritems(path->nodes[level])) {
6146 path->slots[level]++;
6149 ret = walk_up_proc(trans, root, path, wc);
6153 if (path->locks[level]) {
6154 btrfs_tree_unlock(path->nodes[level]);
6155 path->locks[level] = 0;
6157 free_extent_buffer(path->nodes[level]);
6158 path->nodes[level] = NULL;
6166 * drop a subvolume tree.
6168 * this function traverses the tree freeing any blocks that only
6169 * referenced by the tree.
6171 * when a shared tree block is found. this function decreases its
6172 * reference count by one. if update_ref is true, this function
6173 * also make sure backrefs for the shared block and all lower level
6174 * blocks are properly updated.
6176 int btrfs_drop_snapshot(struct btrfs_root *root,
6177 struct btrfs_block_rsv *block_rsv, int update_ref)
6179 struct btrfs_path *path;
6180 struct btrfs_trans_handle *trans;
6181 struct btrfs_root *tree_root = root->fs_info->tree_root;
6182 struct btrfs_root_item *root_item = &root->root_item;
6183 struct walk_control *wc;
6184 struct btrfs_key key;
6189 path = btrfs_alloc_path();
6192 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6195 trans = btrfs_start_transaction(tree_root, 0);
6197 trans->block_rsv = block_rsv;
6199 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
6200 level = btrfs_header_level(root->node);
6201 path->nodes[level] = btrfs_lock_root_node(root);
6202 btrfs_set_lock_blocking(path->nodes[level]);
6203 path->slots[level] = 0;
6204 path->locks[level] = 1;
6205 memset(&wc->update_progress, 0,
6206 sizeof(wc->update_progress));
6208 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
6209 memcpy(&wc->update_progress, &key,
6210 sizeof(wc->update_progress));
6212 level = root_item->drop_level;
6214 path->lowest_level = level;
6215 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6216 path->lowest_level = 0;
6224 * unlock our path, this is safe because only this
6225 * function is allowed to delete this snapshot
6227 btrfs_unlock_up_safe(path, 0);
6229 level = btrfs_header_level(root->node);
6231 btrfs_tree_lock(path->nodes[level]);
6232 btrfs_set_lock_blocking(path->nodes[level]);
6234 ret = btrfs_lookup_extent_info(trans, root,
6235 path->nodes[level]->start,
6236 path->nodes[level]->len,
6240 BUG_ON(wc->refs[level] == 0);
6242 if (level == root_item->drop_level)
6245 btrfs_tree_unlock(path->nodes[level]);
6246 WARN_ON(wc->refs[level] != 1);
6252 wc->shared_level = -1;
6253 wc->stage = DROP_REFERENCE;
6254 wc->update_ref = update_ref;
6256 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6259 ret = walk_down_tree(trans, root, path, wc);
6265 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
6272 BUG_ON(wc->stage != DROP_REFERENCE);
6276 if (wc->stage == DROP_REFERENCE) {
6278 btrfs_node_key(path->nodes[level],
6279 &root_item->drop_progress,
6280 path->slots[level]);
6281 root_item->drop_level = level;
6284 BUG_ON(wc->level == 0);
6285 if (btrfs_should_end_transaction(trans, tree_root)) {
6286 ret = btrfs_update_root(trans, tree_root,
6291 btrfs_end_transaction_throttle(trans, tree_root);
6292 trans = btrfs_start_transaction(tree_root, 0);
6294 trans->block_rsv = block_rsv;
6297 btrfs_release_path(root, path);
6300 ret = btrfs_del_root(trans, tree_root, &root->root_key);
6303 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
6304 ret = btrfs_find_last_root(tree_root, root->root_key.objectid,
6308 ret = btrfs_del_orphan_item(trans, tree_root,
6309 root->root_key.objectid);
6314 if (root->in_radix) {
6315 btrfs_free_fs_root(tree_root->fs_info, root);
6317 free_extent_buffer(root->node);
6318 free_extent_buffer(root->commit_root);
6322 btrfs_end_transaction_throttle(trans, tree_root);
6324 btrfs_free_path(path);
6329 * drop subtree rooted at tree block 'node'.
6331 * NOTE: this function will unlock and release tree block 'node'
6333 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
6334 struct btrfs_root *root,
6335 struct extent_buffer *node,
6336 struct extent_buffer *parent)
6338 struct btrfs_path *path;
6339 struct walk_control *wc;
6345 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
6347 path = btrfs_alloc_path();
6350 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6353 btrfs_assert_tree_locked(parent);
6354 parent_level = btrfs_header_level(parent);
6355 extent_buffer_get(parent);
6356 path->nodes[parent_level] = parent;
6357 path->slots[parent_level] = btrfs_header_nritems(parent);
6359 btrfs_assert_tree_locked(node);
6360 level = btrfs_header_level(node);
6361 path->nodes[level] = node;
6362 path->slots[level] = 0;
6363 path->locks[level] = 1;
6365 wc->refs[parent_level] = 1;
6366 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
6368 wc->shared_level = -1;
6369 wc->stage = DROP_REFERENCE;
6372 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6375 wret = walk_down_tree(trans, root, path, wc);
6381 wret = walk_up_tree(trans, root, path, wc, parent_level);
6389 btrfs_free_path(path);
6394 static unsigned long calc_ra(unsigned long start, unsigned long last,
6397 return min(last, start + nr - 1);
6400 static noinline int relocate_inode_pages(struct inode *inode, u64 start,
6405 unsigned long first_index;
6406 unsigned long last_index;
6409 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6410 struct file_ra_state *ra;
6411 struct btrfs_ordered_extent *ordered;
6412 unsigned int total_read = 0;
6413 unsigned int total_dirty = 0;
6416 ra = kzalloc(sizeof(*ra), GFP_NOFS);
6418 mutex_lock(&inode->i_mutex);
6419 first_index = start >> PAGE_CACHE_SHIFT;
6420 last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
6422 /* make sure the dirty trick played by the caller work */
6423 ret = invalidate_inode_pages2_range(inode->i_mapping,
6424 first_index, last_index);
6428 file_ra_state_init(ra, inode->i_mapping);
6430 for (i = first_index ; i <= last_index; i++) {
6431 if (total_read % ra->ra_pages == 0) {
6432 btrfs_force_ra(inode->i_mapping, ra, NULL, i,
6433 calc_ra(i, last_index, ra->ra_pages));
6437 if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode))
6439 page = grab_cache_page(inode->i_mapping, i);
6444 if (!PageUptodate(page)) {
6445 btrfs_readpage(NULL, page);
6447 if (!PageUptodate(page)) {
6449 page_cache_release(page);
6454 wait_on_page_writeback(page);
6456 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
6457 page_end = page_start + PAGE_CACHE_SIZE - 1;
6458 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
6460 ordered = btrfs_lookup_ordered_extent(inode, page_start);
6462 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
6464 page_cache_release(page);
6465 btrfs_start_ordered_extent(inode, ordered, 1);
6466 btrfs_put_ordered_extent(ordered);
6469 set_page_extent_mapped(page);
6471 if (i == first_index)
6472 set_extent_bits(io_tree, page_start, page_end,
6473 EXTENT_BOUNDARY, GFP_NOFS);
6474 btrfs_set_extent_delalloc(inode, page_start, page_end);
6476 set_page_dirty(page);
6479 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
6481 page_cache_release(page);
6486 mutex_unlock(&inode->i_mutex);
6487 balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty);
6491 static noinline int relocate_data_extent(struct inode *reloc_inode,
6492 struct btrfs_key *extent_key,
6495 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
6496 struct extent_map_tree *em_tree = &BTRFS_I(reloc_inode)->extent_tree;
6497 struct extent_map *em;
6498 u64 start = extent_key->objectid - offset;
6499 u64 end = start + extent_key->offset - 1;
6501 em = alloc_extent_map(GFP_NOFS);
6502 BUG_ON(!em || IS_ERR(em));
6505 em->len = extent_key->offset;
6506 em->block_len = extent_key->offset;
6507 em->block_start = extent_key->objectid;
6508 em->bdev = root->fs_info->fs_devices->latest_bdev;
6509 set_bit(EXTENT_FLAG_PINNED, &em->flags);
6511 /* setup extent map to cheat btrfs_readpage */
6512 lock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
6515 write_lock(&em_tree->lock);
6516 ret = add_extent_mapping(em_tree, em);
6517 write_unlock(&em_tree->lock);
6518 if (ret != -EEXIST) {
6519 free_extent_map(em);
6522 btrfs_drop_extent_cache(reloc_inode, start, end, 0);
6524 unlock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
6526 return relocate_inode_pages(reloc_inode, start, extent_key->offset);
6529 struct btrfs_ref_path {
6531 u64 nodes[BTRFS_MAX_LEVEL];
6533 u64 root_generation;
6540 struct btrfs_key node_keys[BTRFS_MAX_LEVEL];
6541 u64 new_nodes[BTRFS_MAX_LEVEL];
6544 struct disk_extent {
6555 static int is_cowonly_root(u64 root_objectid)
6557 if (root_objectid == BTRFS_ROOT_TREE_OBJECTID ||
6558 root_objectid == BTRFS_EXTENT_TREE_OBJECTID ||
6559 root_objectid == BTRFS_CHUNK_TREE_OBJECTID ||
6560 root_objectid == BTRFS_DEV_TREE_OBJECTID ||
6561 root_objectid == BTRFS_TREE_LOG_OBJECTID ||
6562 root_objectid == BTRFS_CSUM_TREE_OBJECTID)
6567 static noinline int __next_ref_path(struct btrfs_trans_handle *trans,
6568 struct btrfs_root *extent_root,
6569 struct btrfs_ref_path *ref_path,
6572 struct extent_buffer *leaf;
6573 struct btrfs_path *path;
6574 struct btrfs_extent_ref *ref;
6575 struct btrfs_key key;
6576 struct btrfs_key found_key;
6582 path = btrfs_alloc_path();
6587 ref_path->lowest_level = -1;
6588 ref_path->current_level = -1;
6589 ref_path->shared_level = -1;
6593 level = ref_path->current_level - 1;
6594 while (level >= -1) {
6596 if (level < ref_path->lowest_level)
6600 bytenr = ref_path->nodes[level];
6602 bytenr = ref_path->extent_start;
6603 BUG_ON(bytenr == 0);
6605 parent = ref_path->nodes[level + 1];
6606 ref_path->nodes[level + 1] = 0;
6607 ref_path->current_level = level;
6608 BUG_ON(parent == 0);
6610 key.objectid = bytenr;
6611 key.offset = parent + 1;
6612 key.type = BTRFS_EXTENT_REF_KEY;
6614 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
6619 leaf = path->nodes[0];
6620 nritems = btrfs_header_nritems(leaf);
6621 if (path->slots[0] >= nritems) {
6622 ret = btrfs_next_leaf(extent_root, path);
6627 leaf = path->nodes[0];
6630 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6631 if (found_key.objectid == bytenr &&
6632 found_key.type == BTRFS_EXTENT_REF_KEY) {
6633 if (level < ref_path->shared_level)
6634 ref_path->shared_level = level;
6639 btrfs_release_path(extent_root, path);
6642 /* reached lowest level */
6646 level = ref_path->current_level;
6647 while (level < BTRFS_MAX_LEVEL - 1) {
6651 bytenr = ref_path->nodes[level];
6653 bytenr = ref_path->extent_start;
6655 BUG_ON(bytenr == 0);
6657 key.objectid = bytenr;
6659 key.type = BTRFS_EXTENT_REF_KEY;
6661 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
6665 leaf = path->nodes[0];
6666 nritems = btrfs_header_nritems(leaf);
6667 if (path->slots[0] >= nritems) {
6668 ret = btrfs_next_leaf(extent_root, path);
6672 /* the extent was freed by someone */
6673 if (ref_path->lowest_level == level)
6675 btrfs_release_path(extent_root, path);
6678 leaf = path->nodes[0];
6681 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6682 if (found_key.objectid != bytenr ||
6683 found_key.type != BTRFS_EXTENT_REF_KEY) {
6684 /* the extent was freed by someone */
6685 if (ref_path->lowest_level == level) {
6689 btrfs_release_path(extent_root, path);
6693 ref = btrfs_item_ptr(leaf, path->slots[0],
6694 struct btrfs_extent_ref);
6695 ref_objectid = btrfs_ref_objectid(leaf, ref);
6696 if (ref_objectid < BTRFS_FIRST_FREE_OBJECTID) {
6698 level = (int)ref_objectid;
6699 BUG_ON(level >= BTRFS_MAX_LEVEL);
6700 ref_path->lowest_level = level;
6701 ref_path->current_level = level;
6702 ref_path->nodes[level] = bytenr;
6704 WARN_ON(ref_objectid != level);
6707 WARN_ON(level != -1);
6711 if (ref_path->lowest_level == level) {
6712 ref_path->owner_objectid = ref_objectid;
6713 ref_path->num_refs = btrfs_ref_num_refs(leaf, ref);
6717 * the block is tree root or the block isn't in reference
6720 if (found_key.objectid == found_key.offset ||
6721 is_cowonly_root(btrfs_ref_root(leaf, ref))) {
6722 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
6723 ref_path->root_generation =
6724 btrfs_ref_generation(leaf, ref);
6726 /* special reference from the tree log */
6727 ref_path->nodes[0] = found_key.offset;
6728 ref_path->current_level = 0;
6735 BUG_ON(ref_path->nodes[level] != 0);
6736 ref_path->nodes[level] = found_key.offset;
6737 ref_path->current_level = level;
6740 * the reference was created in the running transaction,
6741 * no need to continue walking up.
6743 if (btrfs_ref_generation(leaf, ref) == trans->transid) {
6744 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
6745 ref_path->root_generation =
6746 btrfs_ref_generation(leaf, ref);
6751 btrfs_release_path(extent_root, path);
6754 /* reached max tree level, but no tree root found. */
6757 btrfs_free_path(path);
6761 static int btrfs_first_ref_path(struct btrfs_trans_handle *trans,
6762 struct btrfs_root *extent_root,
6763 struct btrfs_ref_path *ref_path,
6766 memset(ref_path, 0, sizeof(*ref_path));
6767 ref_path->extent_start = extent_start;
6769 return __next_ref_path(trans, extent_root, ref_path, 1);
6772 static int btrfs_next_ref_path(struct btrfs_trans_handle *trans,
6773 struct btrfs_root *extent_root,
6774 struct btrfs_ref_path *ref_path)
6776 return __next_ref_path(trans, extent_root, ref_path, 0);
6779 static noinline int get_new_locations(struct inode *reloc_inode,
6780 struct btrfs_key *extent_key,
6781 u64 offset, int no_fragment,
6782 struct disk_extent **extents,
6785 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
6786 struct btrfs_path *path;
6787 struct btrfs_file_extent_item *fi;
6788 struct extent_buffer *leaf;
6789 struct disk_extent *exts = *extents;
6790 struct btrfs_key found_key;
6795 int max = *nr_extents;
6798 WARN_ON(!no_fragment && *extents);
6801 exts = kmalloc(sizeof(*exts) * max, GFP_NOFS);
6806 path = btrfs_alloc_path();
6809 cur_pos = extent_key->objectid - offset;
6810 last_byte = extent_key->objectid + extent_key->offset;
6811 ret = btrfs_lookup_file_extent(NULL, root, path, reloc_inode->i_ino,
6821 leaf = path->nodes[0];
6822 nritems = btrfs_header_nritems(leaf);
6823 if (path->slots[0] >= nritems) {
6824 ret = btrfs_next_leaf(root, path);
6829 leaf = path->nodes[0];
6832 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6833 if (found_key.offset != cur_pos ||
6834 found_key.type != BTRFS_EXTENT_DATA_KEY ||
6835 found_key.objectid != reloc_inode->i_ino)
6838 fi = btrfs_item_ptr(leaf, path->slots[0],
6839 struct btrfs_file_extent_item);
6840 if (btrfs_file_extent_type(leaf, fi) !=
6841 BTRFS_FILE_EXTENT_REG ||
6842 btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
6846 struct disk_extent *old = exts;
6848 exts = kzalloc(sizeof(*exts) * max, GFP_NOFS);
6849 memcpy(exts, old, sizeof(*exts) * nr);
6850 if (old != *extents)
6854 exts[nr].disk_bytenr =
6855 btrfs_file_extent_disk_bytenr(leaf, fi);
6856 exts[nr].disk_num_bytes =
6857 btrfs_file_extent_disk_num_bytes(leaf, fi);
6858 exts[nr].offset = btrfs_file_extent_offset(leaf, fi);
6859 exts[nr].num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
6860 exts[nr].ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
6861 exts[nr].compression = btrfs_file_extent_compression(leaf, fi);
6862 exts[nr].encryption = btrfs_file_extent_encryption(leaf, fi);
6863 exts[nr].other_encoding = btrfs_file_extent_other_encoding(leaf,
6865 BUG_ON(exts[nr].offset > 0);
6866 BUG_ON(exts[nr].compression || exts[nr].encryption);
6867 BUG_ON(exts[nr].num_bytes != exts[nr].disk_num_bytes);
6869 cur_pos += exts[nr].num_bytes;
6872 if (cur_pos + offset >= last_byte)
6882 BUG_ON(cur_pos + offset > last_byte);
6883 if (cur_pos + offset < last_byte) {
6889 btrfs_free_path(path);
6891 if (exts != *extents)
6900 static noinline int replace_one_extent(struct btrfs_trans_handle *trans,
6901 struct btrfs_root *root,
6902 struct btrfs_path *path,
6903 struct btrfs_key *extent_key,
6904 struct btrfs_key *leaf_key,
6905 struct btrfs_ref_path *ref_path,
6906 struct disk_extent *new_extents,
6909 struct extent_buffer *leaf;
6910 struct btrfs_file_extent_item *fi;
6911 struct inode *inode = NULL;
6912 struct btrfs_key key;
6917 u64 search_end = (u64)-1;
6920 int extent_locked = 0;
6924 memcpy(&key, leaf_key, sizeof(key));
6925 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
6926 if (key.objectid < ref_path->owner_objectid ||
6927 (key.objectid == ref_path->owner_objectid &&
6928 key.type < BTRFS_EXTENT_DATA_KEY)) {
6929 key.objectid = ref_path->owner_objectid;
6930 key.type = BTRFS_EXTENT_DATA_KEY;
6936 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
6940 leaf = path->nodes[0];
6941 nritems = btrfs_header_nritems(leaf);
6943 if (extent_locked && ret > 0) {
6945 * the file extent item was modified by someone
6946 * before the extent got locked.
6948 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
6949 lock_end, GFP_NOFS);
6953 if (path->slots[0] >= nritems) {
6954 if (++nr_scaned > 2)
6957 BUG_ON(extent_locked);
6958 ret = btrfs_next_leaf(root, path);
6963 leaf = path->nodes[0];
6964 nritems = btrfs_header_nritems(leaf);
6967 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
6969 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
6970 if ((key.objectid > ref_path->owner_objectid) ||
6971 (key.objectid == ref_path->owner_objectid &&
6972 key.type > BTRFS_EXTENT_DATA_KEY) ||
6973 key.offset >= search_end)
6977 if (inode && key.objectid != inode->i_ino) {
6978 BUG_ON(extent_locked);
6979 btrfs_release_path(root, path);
6980 mutex_unlock(&inode->i_mutex);
6986 if (key.type != BTRFS_EXTENT_DATA_KEY) {
6991 fi = btrfs_item_ptr(leaf, path->slots[0],
6992 struct btrfs_file_extent_item);
6993 extent_type = btrfs_file_extent_type(leaf, fi);
6994 if ((extent_type != BTRFS_FILE_EXTENT_REG &&
6995 extent_type != BTRFS_FILE_EXTENT_PREALLOC) ||
6996 (btrfs_file_extent_disk_bytenr(leaf, fi) !=
6997 extent_key->objectid)) {
7003 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
7004 ext_offset = btrfs_file_extent_offset(leaf, fi);
7006 if (search_end == (u64)-1) {
7007 search_end = key.offset - ext_offset +
7008 btrfs_file_extent_ram_bytes(leaf, fi);
7011 if (!extent_locked) {
7012 lock_start = key.offset;
7013 lock_end = lock_start + num_bytes - 1;
7015 if (lock_start > key.offset ||
7016 lock_end + 1 < key.offset + num_bytes) {
7017 unlock_extent(&BTRFS_I(inode)->io_tree,
7018 lock_start, lock_end, GFP_NOFS);
7024 btrfs_release_path(root, path);
7026 inode = btrfs_iget_locked(root->fs_info->sb,
7027 key.objectid, root);
7028 if (inode->i_state & I_NEW) {
7029 BTRFS_I(inode)->root = root;
7030 BTRFS_I(inode)->location.objectid =
7032 BTRFS_I(inode)->location.type =
7033 BTRFS_INODE_ITEM_KEY;
7034 BTRFS_I(inode)->location.offset = 0;
7035 btrfs_read_locked_inode(inode);
7036 unlock_new_inode(inode);
7039 * some code call btrfs_commit_transaction while
7040 * holding the i_mutex, so we can't use mutex_lock
7043 if (is_bad_inode(inode) ||
7044 !mutex_trylock(&inode->i_mutex)) {
7047 key.offset = (u64)-1;
7052 if (!extent_locked) {
7053 struct btrfs_ordered_extent *ordered;
7055 btrfs_release_path(root, path);
7057 lock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7058 lock_end, GFP_NOFS);
7059 ordered = btrfs_lookup_first_ordered_extent(inode,
7062 ordered->file_offset <= lock_end &&
7063 ordered->file_offset + ordered->len > lock_start) {
7064 unlock_extent(&BTRFS_I(inode)->io_tree,
7065 lock_start, lock_end, GFP_NOFS);
7066 btrfs_start_ordered_extent(inode, ordered, 1);
7067 btrfs_put_ordered_extent(ordered);
7068 key.offset += num_bytes;
7072 btrfs_put_ordered_extent(ordered);
7078 if (nr_extents == 1) {
7079 /* update extent pointer in place */
7080 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7081 new_extents[0].disk_bytenr);
7082 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7083 new_extents[0].disk_num_bytes);
7084 btrfs_mark_buffer_dirty(leaf);
7086 btrfs_drop_extent_cache(inode, key.offset,
7087 key.offset + num_bytes - 1, 0);
7089 ret = btrfs_inc_extent_ref(trans, root,
7090 new_extents[0].disk_bytenr,
7091 new_extents[0].disk_num_bytes,
7093 root->root_key.objectid,
7098 ret = btrfs_free_extent(trans, root,
7099 extent_key->objectid,
7102 btrfs_header_owner(leaf),
7103 btrfs_header_generation(leaf),
7107 btrfs_release_path(root, path);
7108 key.offset += num_bytes;
7116 * drop old extent pointer at first, then insert the
7117 * new pointers one bye one
7119 btrfs_release_path(root, path);
7120 ret = btrfs_drop_extents(trans, root, inode, key.offset,
7121 key.offset + num_bytes,
7122 key.offset, &alloc_hint);
7125 for (i = 0; i < nr_extents; i++) {
7126 if (ext_offset >= new_extents[i].num_bytes) {
7127 ext_offset -= new_extents[i].num_bytes;
7130 extent_len = min(new_extents[i].num_bytes -
7131 ext_offset, num_bytes);
7133 ret = btrfs_insert_empty_item(trans, root,
7138 leaf = path->nodes[0];
7139 fi = btrfs_item_ptr(leaf, path->slots[0],
7140 struct btrfs_file_extent_item);
7141 btrfs_set_file_extent_generation(leaf, fi,
7143 btrfs_set_file_extent_type(leaf, fi,
7144 BTRFS_FILE_EXTENT_REG);
7145 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7146 new_extents[i].disk_bytenr);
7147 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7148 new_extents[i].disk_num_bytes);
7149 btrfs_set_file_extent_ram_bytes(leaf, fi,
7150 new_extents[i].ram_bytes);
7152 btrfs_set_file_extent_compression(leaf, fi,
7153 new_extents[i].compression);
7154 btrfs_set_file_extent_encryption(leaf, fi,
7155 new_extents[i].encryption);
7156 btrfs_set_file_extent_other_encoding(leaf, fi,
7157 new_extents[i].other_encoding);
7159 btrfs_set_file_extent_num_bytes(leaf, fi,
7161 ext_offset += new_extents[i].offset;
7162 btrfs_set_file_extent_offset(leaf, fi,
7164 btrfs_mark_buffer_dirty(leaf);
7166 btrfs_drop_extent_cache(inode, key.offset,
7167 key.offset + extent_len - 1, 0);
7169 ret = btrfs_inc_extent_ref(trans, root,
7170 new_extents[i].disk_bytenr,
7171 new_extents[i].disk_num_bytes,
7173 root->root_key.objectid,
7174 trans->transid, key.objectid);
7176 btrfs_release_path(root, path);
7178 inode_add_bytes(inode, extent_len);
7181 num_bytes -= extent_len;
7182 key.offset += extent_len;
7187 BUG_ON(i >= nr_extents);
7191 if (extent_locked) {
7192 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7193 lock_end, GFP_NOFS);
7197 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS &&
7198 key.offset >= search_end)
7205 btrfs_release_path(root, path);
7207 mutex_unlock(&inode->i_mutex);
7208 if (extent_locked) {
7209 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7210 lock_end, GFP_NOFS);
7217 int btrfs_reloc_tree_cache_ref(struct btrfs_trans_handle *trans,
7218 struct btrfs_root *root,
7219 struct extent_buffer *buf, u64 orig_start)
7224 BUG_ON(btrfs_header_generation(buf) != trans->transid);
7225 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
7227 level = btrfs_header_level(buf);
7229 struct btrfs_leaf_ref *ref;
7230 struct btrfs_leaf_ref *orig_ref;
7232 orig_ref = btrfs_lookup_leaf_ref(root, orig_start);
7236 ref = btrfs_alloc_leaf_ref(root, orig_ref->nritems);
7238 btrfs_free_leaf_ref(root, orig_ref);
7242 ref->nritems = orig_ref->nritems;
7243 memcpy(ref->extents, orig_ref->extents,
7244 sizeof(ref->extents[0]) * ref->nritems);
7246 btrfs_free_leaf_ref(root, orig_ref);
7248 ref->root_gen = trans->transid;
7249 ref->bytenr = buf->start;
7250 ref->owner = btrfs_header_owner(buf);
7251 ref->generation = btrfs_header_generation(buf);
7253 ret = btrfs_add_leaf_ref(root, ref, 0);
7255 btrfs_free_leaf_ref(root, ref);
7260 static noinline int invalidate_extent_cache(struct btrfs_root *root,
7261 struct extent_buffer *leaf,
7262 struct btrfs_block_group_cache *group,
7263 struct btrfs_root *target_root)
7265 struct btrfs_key key;
7266 struct inode *inode = NULL;
7267 struct btrfs_file_extent_item *fi;
7268 struct extent_state *cached_state = NULL;
7270 u64 skip_objectid = 0;
7274 nritems = btrfs_header_nritems(leaf);
7275 for (i = 0; i < nritems; i++) {
7276 btrfs_item_key_to_cpu(leaf, &key, i);
7277 if (key.objectid == skip_objectid ||
7278 key.type != BTRFS_EXTENT_DATA_KEY)
7280 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
7281 if (btrfs_file_extent_type(leaf, fi) ==
7282 BTRFS_FILE_EXTENT_INLINE)
7284 if (btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
7286 if (!inode || inode->i_ino != key.objectid) {
7288 inode = btrfs_ilookup(target_root->fs_info->sb,
7289 key.objectid, target_root, 1);
7292 skip_objectid = key.objectid;
7295 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
7297 lock_extent_bits(&BTRFS_I(inode)->io_tree, key.offset,
7298 key.offset + num_bytes - 1, 0, &cached_state,
7300 btrfs_drop_extent_cache(inode, key.offset,
7301 key.offset + num_bytes - 1, 1);
7302 unlock_extent_cached(&BTRFS_I(inode)->io_tree, key.offset,
7303 key.offset + num_bytes - 1, &cached_state,
7311 static noinline int replace_extents_in_leaf(struct btrfs_trans_handle *trans,
7312 struct btrfs_root *root,
7313 struct extent_buffer *leaf,
7314 struct btrfs_block_group_cache *group,
7315 struct inode *reloc_inode)
7317 struct btrfs_key key;
7318 struct btrfs_key extent_key;
7319 struct btrfs_file_extent_item *fi;
7320 struct btrfs_leaf_ref *ref;
7321 struct disk_extent *new_extent;
7330 new_extent = kmalloc(sizeof(*new_extent), GFP_NOFS);
7331 BUG_ON(!new_extent);
7333 ref = btrfs_lookup_leaf_ref(root, leaf->start);
7337 nritems = btrfs_header_nritems(leaf);
7338 for (i = 0; i < nritems; i++) {
7339 btrfs_item_key_to_cpu(leaf, &key, i);
7340 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
7342 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
7343 if (btrfs_file_extent_type(leaf, fi) ==
7344 BTRFS_FILE_EXTENT_INLINE)
7346 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
7347 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
7352 if (bytenr >= group->key.objectid + group->key.offset ||
7353 bytenr + num_bytes <= group->key.objectid)
7356 extent_key.objectid = bytenr;
7357 extent_key.offset = num_bytes;
7358 extent_key.type = BTRFS_EXTENT_ITEM_KEY;
7360 ret = get_new_locations(reloc_inode, &extent_key,
7361 group->key.objectid, 1,
7362 &new_extent, &nr_extent);
7367 BUG_ON(ref->extents[ext_index].bytenr != bytenr);
7368 BUG_ON(ref->extents[ext_index].num_bytes != num_bytes);
7369 ref->extents[ext_index].bytenr = new_extent->disk_bytenr;
7370 ref->extents[ext_index].num_bytes = new_extent->disk_num_bytes;
7372 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7373 new_extent->disk_bytenr);
7374 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7375 new_extent->disk_num_bytes);
7376 btrfs_mark_buffer_dirty(leaf);
7378 ret = btrfs_inc_extent_ref(trans, root,
7379 new_extent->disk_bytenr,
7380 new_extent->disk_num_bytes,
7382 root->root_key.objectid,
7383 trans->transid, key.objectid);
7386 ret = btrfs_free_extent(trans, root,
7387 bytenr, num_bytes, leaf->start,
7388 btrfs_header_owner(leaf),
7389 btrfs_header_generation(leaf),
7395 BUG_ON(ext_index + 1 != ref->nritems);
7396 btrfs_free_leaf_ref(root, ref);
7400 int btrfs_free_reloc_root(struct btrfs_trans_handle *trans,
7401 struct btrfs_root *root)
7403 struct btrfs_root *reloc_root;
7406 if (root->reloc_root) {
7407 reloc_root = root->reloc_root;
7408 root->reloc_root = NULL;
7409 list_add(&reloc_root->dead_list,
7410 &root->fs_info->dead_reloc_roots);
7412 btrfs_set_root_bytenr(&reloc_root->root_item,
7413 reloc_root->node->start);
7414 btrfs_set_root_level(&root->root_item,
7415 btrfs_header_level(reloc_root->node));
7416 memset(&reloc_root->root_item.drop_progress, 0,
7417 sizeof(struct btrfs_disk_key));
7418 reloc_root->root_item.drop_level = 0;
7420 ret = btrfs_update_root(trans, root->fs_info->tree_root,
7421 &reloc_root->root_key,
7422 &reloc_root->root_item);
7428 int btrfs_drop_dead_reloc_roots(struct btrfs_root *root)
7430 struct btrfs_trans_handle *trans;
7431 struct btrfs_root *reloc_root;
7432 struct btrfs_root *prev_root = NULL;
7433 struct list_head dead_roots;
7437 INIT_LIST_HEAD(&dead_roots);
7438 list_splice_init(&root->fs_info->dead_reloc_roots, &dead_roots);
7440 while (!list_empty(&dead_roots)) {
7441 reloc_root = list_entry(dead_roots.prev,
7442 struct btrfs_root, dead_list);
7443 list_del_init(&reloc_root->dead_list);
7445 BUG_ON(reloc_root->commit_root != NULL);
7447 trans = btrfs_join_transaction(root, 1);
7450 mutex_lock(&root->fs_info->drop_mutex);
7451 ret = btrfs_drop_snapshot(trans, reloc_root);
7454 mutex_unlock(&root->fs_info->drop_mutex);
7456 nr = trans->blocks_used;
7457 ret = btrfs_end_transaction(trans, root);
7459 btrfs_btree_balance_dirty(root, nr);
7462 free_extent_buffer(reloc_root->node);
7464 ret = btrfs_del_root(trans, root->fs_info->tree_root,
7465 &reloc_root->root_key);
7467 mutex_unlock(&root->fs_info->drop_mutex);
7469 nr = trans->blocks_used;
7470 ret = btrfs_end_transaction(trans, root);
7472 btrfs_btree_balance_dirty(root, nr);
7475 prev_root = reloc_root;
7478 btrfs_remove_leaf_refs(prev_root, (u64)-1, 0);
7484 int btrfs_add_dead_reloc_root(struct btrfs_root *root)
7486 list_add(&root->dead_list, &root->fs_info->dead_reloc_roots);
7490 int btrfs_cleanup_reloc_trees(struct btrfs_root *root)
7492 struct btrfs_root *reloc_root;
7493 struct btrfs_trans_handle *trans;
7494 struct btrfs_key location;
7498 mutex_lock(&root->fs_info->tree_reloc_mutex);
7499 ret = btrfs_find_dead_roots(root, BTRFS_TREE_RELOC_OBJECTID, NULL);
7501 found = !list_empty(&root->fs_info->dead_reloc_roots);
7502 mutex_unlock(&root->fs_info->tree_reloc_mutex);
7505 trans = btrfs_start_transaction(root, 1);
7507 ret = btrfs_commit_transaction(trans, root);
7511 location.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
7512 location.offset = (u64)-1;
7513 location.type = BTRFS_ROOT_ITEM_KEY;
7515 reloc_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
7516 BUG_ON(!reloc_root);
7517 btrfs_orphan_cleanup(reloc_root);
7521 static noinline int init_reloc_tree(struct btrfs_trans_handle *trans,
7522 struct btrfs_root *root)
7524 struct btrfs_root *reloc_root;
7525 struct extent_buffer *eb;
7526 struct btrfs_root_item *root_item;
7527 struct btrfs_key root_key;
7530 BUG_ON(!root->ref_cows);
7531 if (root->reloc_root)
7534 root_item = kmalloc(sizeof(*root_item), GFP_NOFS);
7537 ret = btrfs_copy_root(trans, root, root->commit_root,
7538 &eb, BTRFS_TREE_RELOC_OBJECTID);
7541 root_key.objectid = BTRFS_TREE_RELOC_OBJECTID;
7542 root_key.offset = root->root_key.objectid;
7543 root_key.type = BTRFS_ROOT_ITEM_KEY;
7545 memcpy(root_item, &root->root_item, sizeof(root_item));
7546 btrfs_set_root_refs(root_item, 0);
7547 btrfs_set_root_bytenr(root_item, eb->start);
7548 btrfs_set_root_level(root_item, btrfs_header_level(eb));
7549 btrfs_set_root_generation(root_item, trans->transid);
7551 btrfs_tree_unlock(eb);
7552 free_extent_buffer(eb);
7554 ret = btrfs_insert_root(trans, root->fs_info->tree_root,
7555 &root_key, root_item);
7559 reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root,
7561 BUG_ON(!reloc_root);
7562 reloc_root->last_trans = trans->transid;
7563 reloc_root->commit_root = NULL;
7564 reloc_root->ref_tree = &root->fs_info->reloc_ref_tree;
7566 root->reloc_root = reloc_root;
7571 * Core function of space balance.
7573 * The idea is using reloc trees to relocate tree blocks in reference
7574 * counted roots. There is one reloc tree for each subvol, and all
7575 * reloc trees share same root key objectid. Reloc trees are snapshots
7576 * of the latest committed roots of subvols (root->commit_root).
7578 * To relocate a tree block referenced by a subvol, there are two steps.
7579 * COW the block through subvol's reloc tree, then update block pointer
7580 * in the subvol to point to the new block. Since all reloc trees share
7581 * same root key objectid, doing special handing for tree blocks owned
7582 * by them is easy. Once a tree block has been COWed in one reloc tree,
7583 * we can use the resulting new block directly when the same block is
7584 * required to COW again through other reloc trees. By this way, relocated
7585 * tree blocks are shared between reloc trees, so they are also shared
7588 static noinline int relocate_one_path(struct btrfs_trans_handle *trans,
7589 struct btrfs_root *root,
7590 struct btrfs_path *path,
7591 struct btrfs_key *first_key,
7592 struct btrfs_ref_path *ref_path,
7593 struct btrfs_block_group_cache *group,
7594 struct inode *reloc_inode)
7596 struct btrfs_root *reloc_root;
7597 struct extent_buffer *eb = NULL;
7598 struct btrfs_key *keys;
7602 int lowest_level = 0;
7605 if (ref_path->owner_objectid < BTRFS_FIRST_FREE_OBJECTID)
7606 lowest_level = ref_path->owner_objectid;
7608 if (!root->ref_cows) {
7609 path->lowest_level = lowest_level;
7610 ret = btrfs_search_slot(trans, root, first_key, path, 0, 1);
7612 path->lowest_level = 0;
7613 btrfs_release_path(root, path);
7617 mutex_lock(&root->fs_info->tree_reloc_mutex);
7618 ret = init_reloc_tree(trans, root);
7620 reloc_root = root->reloc_root;
7622 shared_level = ref_path->shared_level;
7623 ref_path->shared_level = BTRFS_MAX_LEVEL - 1;
7625 keys = ref_path->node_keys;
7626 nodes = ref_path->new_nodes;
7627 memset(&keys[shared_level + 1], 0,
7628 sizeof(*keys) * (BTRFS_MAX_LEVEL - shared_level - 1));
7629 memset(&nodes[shared_level + 1], 0,
7630 sizeof(*nodes) * (BTRFS_MAX_LEVEL - shared_level - 1));
7632 if (nodes[lowest_level] == 0) {
7633 path->lowest_level = lowest_level;
7634 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
7637 for (level = lowest_level; level < BTRFS_MAX_LEVEL; level++) {
7638 eb = path->nodes[level];
7639 if (!eb || eb == reloc_root->node)
7641 nodes[level] = eb->start;
7643 btrfs_item_key_to_cpu(eb, &keys[level], 0);
7645 btrfs_node_key_to_cpu(eb, &keys[level], 0);
7648 ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7649 eb = path->nodes[0];
7650 ret = replace_extents_in_leaf(trans, reloc_root, eb,
7651 group, reloc_inode);
7654 btrfs_release_path(reloc_root, path);
7656 ret = btrfs_merge_path(trans, reloc_root, keys, nodes,
7662 * replace tree blocks in the fs tree with tree blocks in
7665 ret = btrfs_merge_path(trans, root, keys, nodes, lowest_level);
7668 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7669 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
7672 extent_buffer_get(path->nodes[0]);
7673 eb = path->nodes[0];
7674 btrfs_release_path(reloc_root, path);
7675 ret = invalidate_extent_cache(reloc_root, eb, group, root);
7677 free_extent_buffer(eb);
7680 mutex_unlock(&root->fs_info->tree_reloc_mutex);
7681 path->lowest_level = 0;
7685 static noinline int relocate_tree_block(struct btrfs_trans_handle *trans,
7686 struct btrfs_root *root,
7687 struct btrfs_path *path,
7688 struct btrfs_key *first_key,
7689 struct btrfs_ref_path *ref_path)
7693 ret = relocate_one_path(trans, root, path, first_key,
7694 ref_path, NULL, NULL);
7700 static noinline int del_extent_zero(struct btrfs_trans_handle *trans,
7701 struct btrfs_root *extent_root,
7702 struct btrfs_path *path,
7703 struct btrfs_key *extent_key)
7707 ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1);
7710 ret = btrfs_del_item(trans, extent_root, path);
7712 btrfs_release_path(extent_root, path);
7716 static noinline struct btrfs_root *read_ref_root(struct btrfs_fs_info *fs_info,
7717 struct btrfs_ref_path *ref_path)
7719 struct btrfs_key root_key;
7721 root_key.objectid = ref_path->root_objectid;
7722 root_key.type = BTRFS_ROOT_ITEM_KEY;
7723 if (is_cowonly_root(ref_path->root_objectid))
7724 root_key.offset = 0;
7726 root_key.offset = (u64)-1;
7728 return btrfs_read_fs_root_no_name(fs_info, &root_key);
7731 static noinline int relocate_one_extent(struct btrfs_root *extent_root,
7732 struct btrfs_path *path,
7733 struct btrfs_key *extent_key,
7734 struct btrfs_block_group_cache *group,
7735 struct inode *reloc_inode, int pass)
7737 struct btrfs_trans_handle *trans;
7738 struct btrfs_root *found_root;
7739 struct btrfs_ref_path *ref_path = NULL;
7740 struct disk_extent *new_extents = NULL;
7745 struct btrfs_key first_key;
7749 trans = btrfs_start_transaction(extent_root, 1);
7752 if (extent_key->objectid == 0) {
7753 ret = del_extent_zero(trans, extent_root, path, extent_key);
7757 ref_path = kmalloc(sizeof(*ref_path), GFP_NOFS);
7763 for (loops = 0; ; loops++) {
7765 ret = btrfs_first_ref_path(trans, extent_root, ref_path,
7766 extent_key->objectid);
7768 ret = btrfs_next_ref_path(trans, extent_root, ref_path);
7775 if (ref_path->root_objectid == BTRFS_TREE_LOG_OBJECTID ||
7776 ref_path->root_objectid == BTRFS_TREE_RELOC_OBJECTID)
7779 found_root = read_ref_root(extent_root->fs_info, ref_path);
7780 BUG_ON(!found_root);
7782 * for reference counted tree, only process reference paths
7783 * rooted at the latest committed root.
7785 if (found_root->ref_cows &&
7786 ref_path->root_generation != found_root->root_key.offset)
7789 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7792 * copy data extents to new locations
7794 u64 group_start = group->key.objectid;
7795 ret = relocate_data_extent(reloc_inode,
7804 level = ref_path->owner_objectid;
7807 if (prev_block != ref_path->nodes[level]) {
7808 struct extent_buffer *eb;
7809 u64 block_start = ref_path->nodes[level];
7810 u64 block_size = btrfs_level_size(found_root, level);
7812 eb = read_tree_block(found_root, block_start,
7814 btrfs_tree_lock(eb);
7815 BUG_ON(level != btrfs_header_level(eb));
7818 btrfs_item_key_to_cpu(eb, &first_key, 0);
7820 btrfs_node_key_to_cpu(eb, &first_key, 0);
7822 btrfs_tree_unlock(eb);
7823 free_extent_buffer(eb);
7824 prev_block = block_start;
7827 mutex_lock(&extent_root->fs_info->trans_mutex);
7828 btrfs_record_root_in_trans(found_root);
7829 mutex_unlock(&extent_root->fs_info->trans_mutex);
7830 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7832 * try to update data extent references while
7833 * keeping metadata shared between snapshots.
7836 ret = relocate_one_path(trans, found_root,
7837 path, &first_key, ref_path,
7838 group, reloc_inode);
7844 * use fallback method to process the remaining
7848 u64 group_start = group->key.objectid;
7849 new_extents = kmalloc(sizeof(*new_extents),
7852 ret = get_new_locations(reloc_inode,
7860 ret = replace_one_extent(trans, found_root,
7862 &first_key, ref_path,
7863 new_extents, nr_extents);
7865 ret = relocate_tree_block(trans, found_root, path,
7866 &first_key, ref_path);
7873 btrfs_end_transaction(trans, extent_root);
7880 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
7883 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
7884 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
7886 num_devices = root->fs_info->fs_devices->rw_devices;
7887 if (num_devices == 1) {
7888 stripped |= BTRFS_BLOCK_GROUP_DUP;
7889 stripped = flags & ~stripped;
7891 /* turn raid0 into single device chunks */
7892 if (flags & BTRFS_BLOCK_GROUP_RAID0)
7895 /* turn mirroring into duplication */
7896 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
7897 BTRFS_BLOCK_GROUP_RAID10))
7898 return stripped | BTRFS_BLOCK_GROUP_DUP;
7901 /* they already had raid on here, just return */
7902 if (flags & stripped)
7905 stripped |= BTRFS_BLOCK_GROUP_DUP;
7906 stripped = flags & ~stripped;
7908 /* switch duplicated blocks with raid1 */
7909 if (flags & BTRFS_BLOCK_GROUP_DUP)
7910 return stripped | BTRFS_BLOCK_GROUP_RAID1;
7912 /* turn single device chunks into raid0 */
7913 return stripped | BTRFS_BLOCK_GROUP_RAID0;
7918 static int set_block_group_ro(struct btrfs_block_group_cache *cache)
7920 struct btrfs_space_info *sinfo = cache->space_info;
7927 spin_lock(&sinfo->lock);
7928 spin_lock(&cache->lock);
7929 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
7930 cache->bytes_super - btrfs_block_group_used(&cache->item);
7932 if (sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned +
7933 sinfo->bytes_may_use + sinfo->bytes_readonly +
7934 cache->reserved_pinned + num_bytes < sinfo->total_bytes) {
7935 sinfo->bytes_readonly += num_bytes;
7936 sinfo->bytes_reserved += cache->reserved_pinned;
7937 cache->reserved_pinned = 0;
7941 spin_unlock(&cache->lock);
7942 spin_unlock(&sinfo->lock);
7946 int btrfs_set_block_group_ro(struct btrfs_root *root,
7947 struct btrfs_block_group_cache *cache)
7950 struct btrfs_trans_handle *trans;
7956 trans = btrfs_join_transaction(root, 1);
7957 BUG_ON(IS_ERR(trans));
7959 alloc_flags = update_block_group_flags(root, cache->flags);
7960 if (alloc_flags != cache->flags)
7961 do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
7963 ret = set_block_group_ro(cache);
7966 alloc_flags = get_alloc_profile(root, cache->space_info->flags);
7967 ret = do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
7970 ret = set_block_group_ro(cache);
7972 btrfs_end_transaction(trans, root);
7976 int btrfs_set_block_group_rw(struct btrfs_root *root,
7977 struct btrfs_block_group_cache *cache)
7979 struct btrfs_space_info *sinfo = cache->space_info;
7984 spin_lock(&sinfo->lock);
7985 spin_lock(&cache->lock);
7986 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
7987 cache->bytes_super - btrfs_block_group_used(&cache->item);
7988 sinfo->bytes_readonly -= num_bytes;
7990 spin_unlock(&cache->lock);
7991 spin_unlock(&sinfo->lock);
7996 * checks to see if its even possible to relocate this block group.
7998 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
7999 * ok to go ahead and try.
8001 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
8003 struct btrfs_block_group_cache *block_group;
8004 struct btrfs_space_info *space_info;
8005 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
8006 struct btrfs_device *device;
8010 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
8012 /* odd, couldn't find the block group, leave it alone */
8016 /* no bytes used, we're good */
8017 if (!btrfs_block_group_used(&block_group->item))
8020 space_info = block_group->space_info;
8021 spin_lock(&space_info->lock);
8023 full = space_info->full;
8026 * if this is the last block group we have in this space, we can't
8027 * relocate it unless we're able to allocate a new chunk below.
8029 * Otherwise, we need to make sure we have room in the space to handle
8030 * all of the extents from this block group. If we can, we're good
8032 if ((space_info->total_bytes != block_group->key.offset) &&
8033 (space_info->bytes_used + space_info->bytes_reserved +
8034 space_info->bytes_pinned + space_info->bytes_readonly +
8035 btrfs_block_group_used(&block_group->item) <
8036 space_info->total_bytes)) {
8037 spin_unlock(&space_info->lock);
8040 spin_unlock(&space_info->lock);
8043 * ok we don't have enough space, but maybe we have free space on our
8044 * devices to allocate new chunks for relocation, so loop through our
8045 * alloc devices and guess if we have enough space. However, if we
8046 * were marked as full, then we know there aren't enough chunks, and we
8053 mutex_lock(&root->fs_info->chunk_mutex);
8054 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
8055 u64 min_free = btrfs_block_group_used(&block_group->item);
8056 u64 dev_offset, max_avail;
8059 * check to make sure we can actually find a chunk with enough
8060 * space to fit our block group in.
8062 if (device->total_bytes > device->bytes_used + min_free) {
8063 ret = find_free_dev_extent(NULL, device, min_free,
8064 &dev_offset, &max_avail);
8070 mutex_unlock(&root->fs_info->chunk_mutex);
8072 btrfs_put_block_group(block_group);
8076 static int find_first_block_group(struct btrfs_root *root,
8077 struct btrfs_path *path, struct btrfs_key *key)
8080 struct btrfs_key found_key;
8081 struct extent_buffer *leaf;
8084 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
8089 slot = path->slots[0];
8090 leaf = path->nodes[0];
8091 if (slot >= btrfs_header_nritems(leaf)) {
8092 ret = btrfs_next_leaf(root, path);
8099 btrfs_item_key_to_cpu(leaf, &found_key, slot);
8101 if (found_key.objectid >= key->objectid &&
8102 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
8112 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
8114 struct btrfs_block_group_cache *block_group;
8118 struct inode *inode;
8120 block_group = btrfs_lookup_first_block_group(info, last);
8121 while (block_group) {
8122 spin_lock(&block_group->lock);
8123 if (block_group->iref)
8125 spin_unlock(&block_group->lock);
8126 block_group = next_block_group(info->tree_root,
8136 inode = block_group->inode;
8137 block_group->iref = 0;
8138 block_group->inode = NULL;
8139 spin_unlock(&block_group->lock);
8141 last = block_group->key.objectid + block_group->key.offset;
8142 btrfs_put_block_group(block_group);
8146 int btrfs_free_block_groups(struct btrfs_fs_info *info)
8148 struct btrfs_block_group_cache *block_group;
8149 struct btrfs_space_info *space_info;
8150 struct btrfs_caching_control *caching_ctl;
8153 down_write(&info->extent_commit_sem);
8154 while (!list_empty(&info->caching_block_groups)) {
8155 caching_ctl = list_entry(info->caching_block_groups.next,
8156 struct btrfs_caching_control, list);
8157 list_del(&caching_ctl->list);
8158 put_caching_control(caching_ctl);
8160 up_write(&info->extent_commit_sem);
8162 spin_lock(&info->block_group_cache_lock);
8163 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
8164 block_group = rb_entry(n, struct btrfs_block_group_cache,
8166 rb_erase(&block_group->cache_node,
8167 &info->block_group_cache_tree);
8168 spin_unlock(&info->block_group_cache_lock);
8170 down_write(&block_group->space_info->groups_sem);
8171 list_del(&block_group->list);
8172 up_write(&block_group->space_info->groups_sem);
8174 if (block_group->cached == BTRFS_CACHE_STARTED)
8175 wait_block_group_cache_done(block_group);
8177 btrfs_remove_free_space_cache(block_group);
8178 btrfs_put_block_group(block_group);
8180 spin_lock(&info->block_group_cache_lock);
8182 spin_unlock(&info->block_group_cache_lock);
8184 /* now that all the block groups are freed, go through and
8185 * free all the space_info structs. This is only called during
8186 * the final stages of unmount, and so we know nobody is
8187 * using them. We call synchronize_rcu() once before we start,
8188 * just to be on the safe side.
8192 release_global_block_rsv(info);
8194 while(!list_empty(&info->space_info)) {
8195 space_info = list_entry(info->space_info.next,
8196 struct btrfs_space_info,
8198 if (space_info->bytes_pinned > 0 ||
8199 space_info->bytes_reserved > 0) {
8201 dump_space_info(space_info, 0, 0);
8203 list_del(&space_info->list);
8209 static void __link_block_group(struct btrfs_space_info *space_info,
8210 struct btrfs_block_group_cache *cache)
8212 int index = get_block_group_index(cache);
8214 down_write(&space_info->groups_sem);
8215 list_add_tail(&cache->list, &space_info->block_groups[index]);
8216 up_write(&space_info->groups_sem);
8219 int btrfs_read_block_groups(struct btrfs_root *root)
8221 struct btrfs_path *path;
8223 struct btrfs_block_group_cache *cache;
8224 struct btrfs_fs_info *info = root->fs_info;
8225 struct btrfs_space_info *space_info;
8226 struct btrfs_key key;
8227 struct btrfs_key found_key;
8228 struct extent_buffer *leaf;
8232 root = info->extent_root;
8235 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
8236 path = btrfs_alloc_path();
8240 cache_gen = btrfs_super_cache_generation(&root->fs_info->super_copy);
8241 if (cache_gen != 0 &&
8242 btrfs_super_generation(&root->fs_info->super_copy) != cache_gen)
8244 if (btrfs_test_opt(root, CLEAR_CACHE))
8246 if (!btrfs_test_opt(root, SPACE_CACHE) && cache_gen)
8247 printk(KERN_INFO "btrfs: disk space caching is enabled\n");
8250 ret = find_first_block_group(root, path, &key);
8256 leaf = path->nodes[0];
8257 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
8258 cache = kzalloc(sizeof(*cache), GFP_NOFS);
8264 atomic_set(&cache->count, 1);
8265 spin_lock_init(&cache->lock);
8266 spin_lock_init(&cache->tree_lock);
8267 cache->fs_info = info;
8268 INIT_LIST_HEAD(&cache->list);
8269 INIT_LIST_HEAD(&cache->cluster_list);
8272 cache->disk_cache_state = BTRFS_DC_CLEAR;
8275 * we only want to have 32k of ram per block group for keeping
8276 * track of free space, and if we pass 1/2 of that we want to
8277 * start converting things over to using bitmaps
8279 cache->extents_thresh = ((1024 * 32) / 2) /
8280 sizeof(struct btrfs_free_space);
8282 read_extent_buffer(leaf, &cache->item,
8283 btrfs_item_ptr_offset(leaf, path->slots[0]),
8284 sizeof(cache->item));
8285 memcpy(&cache->key, &found_key, sizeof(found_key));
8287 key.objectid = found_key.objectid + found_key.offset;
8288 btrfs_release_path(root, path);
8289 cache->flags = btrfs_block_group_flags(&cache->item);
8290 cache->sectorsize = root->sectorsize;
8293 * check for two cases, either we are full, and therefore
8294 * don't need to bother with the caching work since we won't
8295 * find any space, or we are empty, and we can just add all
8296 * the space in and be done with it. This saves us _alot_ of
8297 * time, particularly in the full case.
8299 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
8300 exclude_super_stripes(root, cache);
8301 cache->last_byte_to_unpin = (u64)-1;
8302 cache->cached = BTRFS_CACHE_FINISHED;
8303 free_excluded_extents(root, cache);
8304 } else if (btrfs_block_group_used(&cache->item) == 0) {
8305 exclude_super_stripes(root, cache);
8306 cache->last_byte_to_unpin = (u64)-1;
8307 cache->cached = BTRFS_CACHE_FINISHED;
8308 add_new_free_space(cache, root->fs_info,
8310 found_key.objectid +
8312 free_excluded_extents(root, cache);
8315 ret = update_space_info(info, cache->flags, found_key.offset,
8316 btrfs_block_group_used(&cache->item),
8319 cache->space_info = space_info;
8320 spin_lock(&cache->space_info->lock);
8321 cache->space_info->bytes_readonly += cache->bytes_super;
8322 spin_unlock(&cache->space_info->lock);
8324 __link_block_group(space_info, cache);
8326 ret = btrfs_add_block_group_cache(root->fs_info, cache);
8329 set_avail_alloc_bits(root->fs_info, cache->flags);
8330 if (btrfs_chunk_readonly(root, cache->key.objectid))
8331 set_block_group_ro(cache);
8334 list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) {
8335 if (!(get_alloc_profile(root, space_info->flags) &
8336 (BTRFS_BLOCK_GROUP_RAID10 |
8337 BTRFS_BLOCK_GROUP_RAID1 |
8338 BTRFS_BLOCK_GROUP_DUP)))
8341 * avoid allocating from un-mirrored block group if there are
8342 * mirrored block groups.
8344 list_for_each_entry(cache, &space_info->block_groups[3], list)
8345 set_block_group_ro(cache);
8346 list_for_each_entry(cache, &space_info->block_groups[4], list)
8347 set_block_group_ro(cache);
8350 init_global_block_rsv(info);
8353 btrfs_free_path(path);
8357 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
8358 struct btrfs_root *root, u64 bytes_used,
8359 u64 type, u64 chunk_objectid, u64 chunk_offset,
8363 struct btrfs_root *extent_root;
8364 struct btrfs_block_group_cache *cache;
8366 extent_root = root->fs_info->extent_root;
8368 root->fs_info->last_trans_log_full_commit = trans->transid;
8370 cache = kzalloc(sizeof(*cache), GFP_NOFS);
8374 cache->key.objectid = chunk_offset;
8375 cache->key.offset = size;
8376 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
8377 cache->sectorsize = root->sectorsize;
8378 cache->fs_info = root->fs_info;
8381 * we only want to have 32k of ram per block group for keeping track
8382 * of free space, and if we pass 1/2 of that we want to start
8383 * converting things over to using bitmaps
8385 cache->extents_thresh = ((1024 * 32) / 2) /
8386 sizeof(struct btrfs_free_space);
8387 atomic_set(&cache->count, 1);
8388 spin_lock_init(&cache->lock);
8389 spin_lock_init(&cache->tree_lock);
8390 INIT_LIST_HEAD(&cache->list);
8391 INIT_LIST_HEAD(&cache->cluster_list);
8393 btrfs_set_block_group_used(&cache->item, bytes_used);
8394 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
8395 cache->flags = type;
8396 btrfs_set_block_group_flags(&cache->item, type);
8398 cache->last_byte_to_unpin = (u64)-1;
8399 cache->cached = BTRFS_CACHE_FINISHED;
8400 exclude_super_stripes(root, cache);
8402 add_new_free_space(cache, root->fs_info, chunk_offset,
8403 chunk_offset + size);
8405 free_excluded_extents(root, cache);
8407 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
8408 &cache->space_info);
8411 spin_lock(&cache->space_info->lock);
8412 cache->space_info->bytes_readonly += cache->bytes_super;
8413 spin_unlock(&cache->space_info->lock);
8415 __link_block_group(cache->space_info, cache);
8417 ret = btrfs_add_block_group_cache(root->fs_info, cache);
8420 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
8421 sizeof(cache->item));
8424 set_avail_alloc_bits(extent_root->fs_info, type);
8429 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
8430 struct btrfs_root *root, u64 group_start)
8432 struct btrfs_path *path;
8433 struct btrfs_block_group_cache *block_group;
8434 struct btrfs_free_cluster *cluster;
8435 struct btrfs_root *tree_root = root->fs_info->tree_root;
8436 struct btrfs_key key;
8437 struct inode *inode;
8441 root = root->fs_info->extent_root;
8443 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
8444 BUG_ON(!block_group);
8445 BUG_ON(!block_group->ro);
8447 memcpy(&key, &block_group->key, sizeof(key));
8448 if (block_group->flags & (BTRFS_BLOCK_GROUP_DUP |
8449 BTRFS_BLOCK_GROUP_RAID1 |
8450 BTRFS_BLOCK_GROUP_RAID10))
8455 /* make sure this block group isn't part of an allocation cluster */
8456 cluster = &root->fs_info->data_alloc_cluster;
8457 spin_lock(&cluster->refill_lock);
8458 btrfs_return_cluster_to_free_space(block_group, cluster);
8459 spin_unlock(&cluster->refill_lock);
8462 * make sure this block group isn't part of a metadata
8463 * allocation cluster
8465 cluster = &root->fs_info->meta_alloc_cluster;
8466 spin_lock(&cluster->refill_lock);
8467 btrfs_return_cluster_to_free_space(block_group, cluster);
8468 spin_unlock(&cluster->refill_lock);
8470 path = btrfs_alloc_path();
8473 inode = lookup_free_space_inode(root, block_group, path);
8474 if (!IS_ERR(inode)) {
8475 btrfs_orphan_add(trans, inode);
8477 /* One for the block groups ref */
8478 spin_lock(&block_group->lock);
8479 if (block_group->iref) {
8480 block_group->iref = 0;
8481 block_group->inode = NULL;
8482 spin_unlock(&block_group->lock);
8485 spin_unlock(&block_group->lock);
8487 /* One for our lookup ref */
8491 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
8492 key.offset = block_group->key.objectid;
8495 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
8499 btrfs_release_path(tree_root, path);
8501 ret = btrfs_del_item(trans, tree_root, path);
8504 btrfs_release_path(tree_root, path);
8507 spin_lock(&root->fs_info->block_group_cache_lock);
8508 rb_erase(&block_group->cache_node,
8509 &root->fs_info->block_group_cache_tree);
8510 spin_unlock(&root->fs_info->block_group_cache_lock);
8512 down_write(&block_group->space_info->groups_sem);
8514 * we must use list_del_init so people can check to see if they
8515 * are still on the list after taking the semaphore
8517 list_del_init(&block_group->list);
8518 up_write(&block_group->space_info->groups_sem);
8520 if (block_group->cached == BTRFS_CACHE_STARTED)
8521 wait_block_group_cache_done(block_group);
8523 btrfs_remove_free_space_cache(block_group);
8525 spin_lock(&block_group->space_info->lock);
8526 block_group->space_info->total_bytes -= block_group->key.offset;
8527 block_group->space_info->bytes_readonly -= block_group->key.offset;
8528 block_group->space_info->disk_total -= block_group->key.offset * factor;
8529 spin_unlock(&block_group->space_info->lock);
8531 memcpy(&key, &block_group->key, sizeof(key));
8533 btrfs_clear_space_info_full(root->fs_info);
8535 btrfs_put_block_group(block_group);
8536 btrfs_put_block_group(block_group);
8538 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
8544 ret = btrfs_del_item(trans, root, path);
8546 btrfs_free_path(path);